blob: 8698618e56fe394599a1c28bb585541e65dcc02d [file] [log] [blame]
Grant Likelyca632f52011-06-06 01:16:30 -06001/*
Jassi Brar230d42d2009-11-30 07:39:42 +00002 * Copyright (C) 2009 Samsung Electronics Ltd.
3 * Jaswinder Singh <jassi.brar@samsung.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20#include <linux/init.h>
21#include <linux/module.h>
22#include <linux/workqueue.h>
Mark Brownc2573122011-11-10 10:57:32 +000023#include <linux/interrupt.h>
Jassi Brar230d42d2009-11-30 07:39:42 +000024#include <linux/delay.h>
25#include <linux/clk.h>
26#include <linux/dma-mapping.h>
27#include <linux/platform_device.h>
Mark Brownb97b6622011-12-04 00:58:06 +000028#include <linux/pm_runtime.h>
Jassi Brar230d42d2009-11-30 07:39:42 +000029#include <linux/spi/spi.h>
30
31#include <mach/dma.h>
Jassi Brare6b873c2010-01-20 13:49:45 -070032#include <plat/s3c64xx-spi.h>
Jassi Brar230d42d2009-11-30 07:39:42 +000033
Thomas Abrahama5238e32012-07-13 07:15:14 +090034#define MAX_SPI_PORTS 3
35
Jassi Brar230d42d2009-11-30 07:39:42 +000036/* Registers and bit-fields */
37
38#define S3C64XX_SPI_CH_CFG 0x00
39#define S3C64XX_SPI_CLK_CFG 0x04
40#define S3C64XX_SPI_MODE_CFG 0x08
41#define S3C64XX_SPI_SLAVE_SEL 0x0C
42#define S3C64XX_SPI_INT_EN 0x10
43#define S3C64XX_SPI_STATUS 0x14
44#define S3C64XX_SPI_TX_DATA 0x18
45#define S3C64XX_SPI_RX_DATA 0x1C
46#define S3C64XX_SPI_PACKET_CNT 0x20
47#define S3C64XX_SPI_PENDING_CLR 0x24
48#define S3C64XX_SPI_SWAP_CFG 0x28
49#define S3C64XX_SPI_FB_CLK 0x2C
50
51#define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */
52#define S3C64XX_SPI_CH_SW_RST (1<<5)
53#define S3C64XX_SPI_CH_SLAVE (1<<4)
54#define S3C64XX_SPI_CPOL_L (1<<3)
55#define S3C64XX_SPI_CPHA_B (1<<2)
56#define S3C64XX_SPI_CH_RXCH_ON (1<<1)
57#define S3C64XX_SPI_CH_TXCH_ON (1<<0)
58
59#define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9)
60#define S3C64XX_SPI_CLKSEL_SRCSHFT 9
61#define S3C64XX_SPI_ENCLK_ENABLE (1<<8)
62#define S3C64XX_SPI_PSR_MASK 0xff
63
64#define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29)
65#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29)
66#define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29)
67#define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29)
68#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17)
69#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
70#define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
71#define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
72#define S3C64XX_SPI_MODE_RXDMA_ON (1<<2)
73#define S3C64XX_SPI_MODE_TXDMA_ON (1<<1)
74#define S3C64XX_SPI_MODE_4BURST (1<<0)
75
76#define S3C64XX_SPI_SLAVE_AUTO (1<<1)
77#define S3C64XX_SPI_SLAVE_SIG_INACT (1<<0)
78
79#define S3C64XX_SPI_ACT(c) writel(0, (c)->regs + S3C64XX_SPI_SLAVE_SEL)
80
81#define S3C64XX_SPI_DEACT(c) writel(S3C64XX_SPI_SLAVE_SIG_INACT, \
82 (c)->regs + S3C64XX_SPI_SLAVE_SEL)
83
84#define S3C64XX_SPI_INT_TRAILING_EN (1<<6)
85#define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5)
86#define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4)
87#define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3)
88#define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2)
89#define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1)
90#define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0)
91
92#define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5)
93#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4)
94#define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3)
95#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2)
96#define S3C64XX_SPI_ST_RX_FIFORDY (1<<1)
97#define S3C64XX_SPI_ST_TX_FIFORDY (1<<0)
98
99#define S3C64XX_SPI_PACKET_CNT_EN (1<<16)
100
101#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4)
102#define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3)
103#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2)
104#define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1)
105#define S3C64XX_SPI_PND_TRAILING_CLR (1<<0)
106
107#define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7)
108#define S3C64XX_SPI_SWAP_RX_BYTE (1<<6)
109#define S3C64XX_SPI_SWAP_RX_BIT (1<<5)
110#define S3C64XX_SPI_SWAP_RX_EN (1<<4)
111#define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3)
112#define S3C64XX_SPI_SWAP_TX_BYTE (1<<2)
113#define S3C64XX_SPI_SWAP_TX_BIT (1<<1)
114#define S3C64XX_SPI_SWAP_TX_EN (1<<0)
115
116#define S3C64XX_SPI_FBCLK_MSK (3<<0)
117
Thomas Abrahama5238e32012-07-13 07:15:14 +0900118#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
119#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
120 (1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
121#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
122#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
123 FIFO_LVL_MASK(i))
Jassi Brar230d42d2009-11-30 07:39:42 +0000124
125#define S3C64XX_SPI_MAX_TRAILCNT 0x3ff
126#define S3C64XX_SPI_TRAILCNT_OFF 19
127
128#define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT
129
130#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
131
Jassi Brar230d42d2009-11-30 07:39:42 +0000132#define RXBUSY (1<<2)
133#define TXBUSY (1<<3)
134
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900135struct s3c64xx_spi_dma_data {
136 unsigned ch;
137 enum dma_data_direction direction;
138 enum dma_ch dmach;
139};
140
Jassi Brar230d42d2009-11-30 07:39:42 +0000141/**
Thomas Abrahama5238e32012-07-13 07:15:14 +0900142 * struct s3c64xx_spi_info - SPI Controller hardware info
143 * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
144 * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
145 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
146 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
147 * @clk_from_cmu: True, if the controller does not include a clock mux and
148 * prescaler unit.
149 *
150 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
151 * differ in some aspects such as the size of the fifo and spi bus clock
152 * setup. Such differences are specified to the driver using this structure
153 * which is provided as driver data to the driver.
154 */
155struct s3c64xx_spi_port_config {
156 int fifo_lvl_mask[MAX_SPI_PORTS];
157 int rx_lvl_offset;
158 int tx_st_done;
159 bool high_speed;
160 bool clk_from_cmu;
161};
162
163/**
Jassi Brar230d42d2009-11-30 07:39:42 +0000164 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
165 * @clk: Pointer to the spi clock.
Jassi Brarb0d5d6e2010-01-20 13:49:44 -0700166 * @src_clk: Pointer to the clock used to generate SPI signals.
Jassi Brar230d42d2009-11-30 07:39:42 +0000167 * @master: Pointer to the SPI Protocol master.
Jassi Brar230d42d2009-11-30 07:39:42 +0000168 * @cntrlr_info: Platform specific data for the controller this driver manages.
169 * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
Jassi Brar230d42d2009-11-30 07:39:42 +0000170 * @queue: To log SPI xfer requests.
171 * @lock: Controller specific lock.
172 * @state: Set of FLAGS to indicate status.
173 * @rx_dmach: Controller's DMA channel for Rx.
174 * @tx_dmach: Controller's DMA channel for Tx.
175 * @sfr_start: BUS address of SPI controller regs.
176 * @regs: Pointer to ioremap'ed controller registers.
Mark Brownc2573122011-11-10 10:57:32 +0000177 * @irq: interrupt
Jassi Brar230d42d2009-11-30 07:39:42 +0000178 * @xfer_completion: To indicate completion of xfer task.
179 * @cur_mode: Stores the active configuration of the controller.
180 * @cur_bpw: Stores the active bits per word settings.
181 * @cur_speed: Stores the active xfer clock speed.
182 */
183struct s3c64xx_spi_driver_data {
184 void __iomem *regs;
185 struct clk *clk;
Jassi Brarb0d5d6e2010-01-20 13:49:44 -0700186 struct clk *src_clk;
Jassi Brar230d42d2009-11-30 07:39:42 +0000187 struct platform_device *pdev;
188 struct spi_master *master;
Jassi Brarad7de722010-01-20 13:49:44 -0700189 struct s3c64xx_spi_info *cntrlr_info;
Jassi Brar230d42d2009-11-30 07:39:42 +0000190 struct spi_device *tgl_spi;
Jassi Brar230d42d2009-11-30 07:39:42 +0000191 struct list_head queue;
192 spinlock_t lock;
Jassi Brar230d42d2009-11-30 07:39:42 +0000193 unsigned long sfr_start;
194 struct completion xfer_completion;
195 unsigned state;
196 unsigned cur_mode, cur_bpw;
197 unsigned cur_speed;
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900198 struct s3c64xx_spi_dma_data rx_dma;
199 struct s3c64xx_spi_dma_data tx_dma;
Boojin Kim39d3e802011-09-02 09:44:41 +0900200 struct samsung_dma_ops *ops;
Thomas Abrahama5238e32012-07-13 07:15:14 +0900201 struct s3c64xx_spi_port_config *port_conf;
202 unsigned int port_id;
Jassi Brar230d42d2009-11-30 07:39:42 +0000203};
204
205static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
206 .name = "samsung-spi-dma",
207};
208
209static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
210{
Jassi Brar230d42d2009-11-30 07:39:42 +0000211 void __iomem *regs = sdd->regs;
212 unsigned long loops;
213 u32 val;
214
215 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
216
217 val = readl(regs + S3C64XX_SPI_CH_CFG);
218 val |= S3C64XX_SPI_CH_SW_RST;
219 val &= ~S3C64XX_SPI_CH_HS_EN;
220 writel(val, regs + S3C64XX_SPI_CH_CFG);
221
222 /* Flush TxFIFO*/
223 loops = msecs_to_loops(1);
224 do {
225 val = readl(regs + S3C64XX_SPI_STATUS);
Thomas Abrahama5238e32012-07-13 07:15:14 +0900226 } while (TX_FIFO_LVL(val, sdd) && loops--);
Jassi Brar230d42d2009-11-30 07:39:42 +0000227
Mark Brownbe7852a2010-08-23 17:40:56 +0100228 if (loops == 0)
229 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
230
Jassi Brar230d42d2009-11-30 07:39:42 +0000231 /* Flush RxFIFO*/
232 loops = msecs_to_loops(1);
233 do {
234 val = readl(regs + S3C64XX_SPI_STATUS);
Thomas Abrahama5238e32012-07-13 07:15:14 +0900235 if (RX_FIFO_LVL(val, sdd))
Jassi Brar230d42d2009-11-30 07:39:42 +0000236 readl(regs + S3C64XX_SPI_RX_DATA);
237 else
238 break;
239 } while (loops--);
240
Mark Brownbe7852a2010-08-23 17:40:56 +0100241 if (loops == 0)
242 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
243
Jassi Brar230d42d2009-11-30 07:39:42 +0000244 val = readl(regs + S3C64XX_SPI_CH_CFG);
245 val &= ~S3C64XX_SPI_CH_SW_RST;
246 writel(val, regs + S3C64XX_SPI_CH_CFG);
247
248 val = readl(regs + S3C64XX_SPI_MODE_CFG);
249 val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
250 writel(val, regs + S3C64XX_SPI_MODE_CFG);
251
252 val = readl(regs + S3C64XX_SPI_CH_CFG);
253 val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
254 writel(val, regs + S3C64XX_SPI_CH_CFG);
255}
256
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900257static void s3c64xx_spi_dmacb(void *data)
Boojin Kim39d3e802011-09-02 09:44:41 +0900258{
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900259 struct s3c64xx_spi_driver_data *sdd;
260 struct s3c64xx_spi_dma_data *dma = data;
Boojin Kim39d3e802011-09-02 09:44:41 +0900261 unsigned long flags;
262
Kyoungil Kim054ebcc2012-03-10 09:48:46 +0900263 if (dma->direction == DMA_DEV_TO_MEM)
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900264 sdd = container_of(data,
265 struct s3c64xx_spi_driver_data, rx_dma);
266 else
267 sdd = container_of(data,
268 struct s3c64xx_spi_driver_data, tx_dma);
269
Boojin Kim39d3e802011-09-02 09:44:41 +0900270 spin_lock_irqsave(&sdd->lock, flags);
271
Kyoungil Kim054ebcc2012-03-10 09:48:46 +0900272 if (dma->direction == DMA_DEV_TO_MEM) {
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900273 sdd->state &= ~RXBUSY;
274 if (!(sdd->state & TXBUSY))
275 complete(&sdd->xfer_completion);
276 } else {
277 sdd->state &= ~TXBUSY;
278 if (!(sdd->state & RXBUSY))
279 complete(&sdd->xfer_completion);
280 }
Boojin Kim39d3e802011-09-02 09:44:41 +0900281
282 spin_unlock_irqrestore(&sdd->lock, flags);
283}
284
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900285static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
286 unsigned len, dma_addr_t buf)
Boojin Kim39d3e802011-09-02 09:44:41 +0900287{
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900288 struct s3c64xx_spi_driver_data *sdd;
Boojin Kim4969c322012-06-19 13:27:03 +0900289 struct samsung_dma_prep info;
290 struct samsung_dma_config config;
Boojin Kim39d3e802011-09-02 09:44:41 +0900291
Boojin Kim4969c322012-06-19 13:27:03 +0900292 if (dma->direction == DMA_DEV_TO_MEM) {
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900293 sdd = container_of((void *)dma,
294 struct s3c64xx_spi_driver_data, rx_dma);
Boojin Kim4969c322012-06-19 13:27:03 +0900295 config.direction = sdd->rx_dma.direction;
296 config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
297 config.width = sdd->cur_bpw / 8;
298 sdd->ops->config(sdd->rx_dma.ch, &config);
299 } else {
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900300 sdd = container_of((void *)dma,
301 struct s3c64xx_spi_driver_data, tx_dma);
Boojin Kim4969c322012-06-19 13:27:03 +0900302 config.direction = sdd->tx_dma.direction;
303 config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
304 config.width = sdd->cur_bpw / 8;
305 sdd->ops->config(sdd->tx_dma.ch, &config);
306 }
Boojin Kim39d3e802011-09-02 09:44:41 +0900307
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900308 info.cap = DMA_SLAVE;
309 info.len = len;
310 info.fp = s3c64xx_spi_dmacb;
311 info.fp_param = dma;
312 info.direction = dma->direction;
313 info.buf = buf;
Boojin Kim39d3e802011-09-02 09:44:41 +0900314
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900315 sdd->ops->prepare(dma->ch, &info);
316 sdd->ops->trigger(dma->ch);
317}
318
319static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
320{
Boojin Kim4969c322012-06-19 13:27:03 +0900321 struct samsung_dma_req req;
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900322
323 sdd->ops = samsung_dma_get_ops();
324
Boojin Kim4969c322012-06-19 13:27:03 +0900325 req.cap = DMA_SLAVE;
326 req.client = &s3c64xx_spi_dma_client;
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900327
Boojin Kim4969c322012-06-19 13:27:03 +0900328 sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &req);
329 sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &req);
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900330
331 return 1;
Boojin Kim39d3e802011-09-02 09:44:41 +0900332}
333
Jassi Brar230d42d2009-11-30 07:39:42 +0000334static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
335 struct spi_device *spi,
336 struct spi_transfer *xfer, int dma_mode)
337{
Jassi Brar230d42d2009-11-30 07:39:42 +0000338 void __iomem *regs = sdd->regs;
339 u32 modecfg, chcfg;
340
341 modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
342 modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
343
344 chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
345 chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
346
347 if (dma_mode) {
348 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
349 } else {
350 /* Always shift in data in FIFO, even if xfer is Tx only,
351 * this helps setting PCKT_CNT value for generating clocks
352 * as exactly needed.
353 */
354 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
355 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
356 | S3C64XX_SPI_PACKET_CNT_EN,
357 regs + S3C64XX_SPI_PACKET_CNT);
358 }
359
360 if (xfer->tx_buf != NULL) {
361 sdd->state |= TXBUSY;
362 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
363 if (dma_mode) {
364 modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900365 prepare_dma(&sdd->tx_dma, xfer->len, xfer->tx_dma);
Jassi Brar230d42d2009-11-30 07:39:42 +0000366 } else {
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900367 switch (sdd->cur_bpw) {
368 case 32:
369 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
370 xfer->tx_buf, xfer->len / 4);
371 break;
372 case 16:
373 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
374 xfer->tx_buf, xfer->len / 2);
375 break;
376 default:
377 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
378 xfer->tx_buf, xfer->len);
379 break;
380 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000381 }
382 }
383
384 if (xfer->rx_buf != NULL) {
385 sdd->state |= RXBUSY;
386
Thomas Abrahama5238e32012-07-13 07:15:14 +0900387 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
Jassi Brar230d42d2009-11-30 07:39:42 +0000388 && !(sdd->cur_mode & SPI_CPHA))
389 chcfg |= S3C64XX_SPI_CH_HS_EN;
390
391 if (dma_mode) {
392 modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
393 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
394 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
395 | S3C64XX_SPI_PACKET_CNT_EN,
396 regs + S3C64XX_SPI_PACKET_CNT);
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900397 prepare_dma(&sdd->rx_dma, xfer->len, xfer->rx_dma);
Jassi Brar230d42d2009-11-30 07:39:42 +0000398 }
399 }
400
401 writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
402 writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
403}
404
405static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
406 struct spi_device *spi)
407{
408 struct s3c64xx_spi_csinfo *cs;
409
410 if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
411 if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
412 /* Deselect the last toggled device */
413 cs = sdd->tgl_spi->controller_data;
Jassi Brarfa0fcde2010-01-20 13:49:45 -0700414 cs->set_level(cs->line,
415 spi->mode & SPI_CS_HIGH ? 0 : 1);
Jassi Brar230d42d2009-11-30 07:39:42 +0000416 }
417 sdd->tgl_spi = NULL;
418 }
419
420 cs = spi->controller_data;
Jassi Brarfa0fcde2010-01-20 13:49:45 -0700421 cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
Jassi Brar230d42d2009-11-30 07:39:42 +0000422}
423
424static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
425 struct spi_transfer *xfer, int dma_mode)
426{
Jassi Brar230d42d2009-11-30 07:39:42 +0000427 void __iomem *regs = sdd->regs;
428 unsigned long val;
429 int ms;
430
431 /* millisecs to xfer 'len' bytes @ 'cur_speed' */
432 ms = xfer->len * 8 * 1000 / sdd->cur_speed;
Mark Brown9d8f86b2010-09-07 16:37:52 +0100433 ms += 10; /* some tolerance */
Jassi Brar230d42d2009-11-30 07:39:42 +0000434
435 if (dma_mode) {
436 val = msecs_to_jiffies(ms) + 10;
437 val = wait_for_completion_timeout(&sdd->xfer_completion, val);
438 } else {
Jassi Brarc3f139b2010-09-03 10:36:46 +0900439 u32 status;
Jassi Brar230d42d2009-11-30 07:39:42 +0000440 val = msecs_to_loops(ms);
441 do {
Jassi Brarc3f139b2010-09-03 10:36:46 +0900442 status = readl(regs + S3C64XX_SPI_STATUS);
Thomas Abrahama5238e32012-07-13 07:15:14 +0900443 } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
Jassi Brar230d42d2009-11-30 07:39:42 +0000444 }
445
446 if (!val)
447 return -EIO;
448
449 if (dma_mode) {
450 u32 status;
451
452 /*
453 * DmaTx returns after simply writing data in the FIFO,
454 * w/o waiting for real transmission on the bus to finish.
455 * DmaRx returns only after Dma read data from FIFO which
456 * needs bus transmission to finish, so we don't worry if
457 * Xfer involved Rx(with or without Tx).
458 */
459 if (xfer->rx_buf == NULL) {
460 val = msecs_to_loops(10);
461 status = readl(regs + S3C64XX_SPI_STATUS);
Thomas Abrahama5238e32012-07-13 07:15:14 +0900462 while ((TX_FIFO_LVL(status, sdd)
463 || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
Jassi Brar230d42d2009-11-30 07:39:42 +0000464 && --val) {
465 cpu_relax();
466 status = readl(regs + S3C64XX_SPI_STATUS);
467 }
468
469 if (!val)
470 return -EIO;
471 }
472 } else {
Jassi Brar230d42d2009-11-30 07:39:42 +0000473 /* If it was only Tx */
474 if (xfer->rx_buf == NULL) {
475 sdd->state &= ~TXBUSY;
476 return 0;
477 }
478
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900479 switch (sdd->cur_bpw) {
480 case 32:
481 ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
482 xfer->rx_buf, xfer->len / 4);
483 break;
484 case 16:
485 ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
486 xfer->rx_buf, xfer->len / 2);
487 break;
488 default:
489 ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
490 xfer->rx_buf, xfer->len);
491 break;
492 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000493 sdd->state &= ~RXBUSY;
494 }
495
496 return 0;
497}
498
499static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
500 struct spi_device *spi)
501{
502 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
503
504 if (sdd->tgl_spi == spi)
505 sdd->tgl_spi = NULL;
506
Jassi Brarfa0fcde2010-01-20 13:49:45 -0700507 cs->set_level(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
Jassi Brar230d42d2009-11-30 07:39:42 +0000508}
509
510static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
511{
Jassi Brar230d42d2009-11-30 07:39:42 +0000512 void __iomem *regs = sdd->regs;
513 u32 val;
514
515 /* Disable Clock */
Thomas Abrahama5238e32012-07-13 07:15:14 +0900516 if (sdd->port_conf->clk_from_cmu) {
Jassi Brarb42a81c2010-09-29 17:31:33 +0900517 clk_disable(sdd->src_clk);
518 } else {
519 val = readl(regs + S3C64XX_SPI_CLK_CFG);
520 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
521 writel(val, regs + S3C64XX_SPI_CLK_CFG);
522 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000523
524 /* Set Polarity and Phase */
525 val = readl(regs + S3C64XX_SPI_CH_CFG);
526 val &= ~(S3C64XX_SPI_CH_SLAVE |
527 S3C64XX_SPI_CPOL_L |
528 S3C64XX_SPI_CPHA_B);
529
530 if (sdd->cur_mode & SPI_CPOL)
531 val |= S3C64XX_SPI_CPOL_L;
532
533 if (sdd->cur_mode & SPI_CPHA)
534 val |= S3C64XX_SPI_CPHA_B;
535
536 writel(val, regs + S3C64XX_SPI_CH_CFG);
537
538 /* Set Channel & DMA Mode */
539 val = readl(regs + S3C64XX_SPI_MODE_CFG);
540 val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
541 | S3C64XX_SPI_MODE_CH_TSZ_MASK);
542
543 switch (sdd->cur_bpw) {
544 case 32:
545 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900546 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
Jassi Brar230d42d2009-11-30 07:39:42 +0000547 break;
548 case 16:
549 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900550 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
Jassi Brar230d42d2009-11-30 07:39:42 +0000551 break;
552 default:
553 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900554 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
Jassi Brar230d42d2009-11-30 07:39:42 +0000555 break;
556 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000557
558 writel(val, regs + S3C64XX_SPI_MODE_CFG);
559
Thomas Abrahama5238e32012-07-13 07:15:14 +0900560 if (sdd->port_conf->clk_from_cmu) {
Jassi Brarb42a81c2010-09-29 17:31:33 +0900561 /* Configure Clock */
562 /* There is half-multiplier before the SPI */
563 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
564 /* Enable Clock */
565 clk_enable(sdd->src_clk);
566 } else {
567 /* Configure Clock */
568 val = readl(regs + S3C64XX_SPI_CLK_CFG);
569 val &= ~S3C64XX_SPI_PSR_MASK;
570 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
571 & S3C64XX_SPI_PSR_MASK);
572 writel(val, regs + S3C64XX_SPI_CLK_CFG);
Jassi Brar230d42d2009-11-30 07:39:42 +0000573
Jassi Brarb42a81c2010-09-29 17:31:33 +0900574 /* Enable Clock */
575 val = readl(regs + S3C64XX_SPI_CLK_CFG);
576 val |= S3C64XX_SPI_ENCLK_ENABLE;
577 writel(val, regs + S3C64XX_SPI_CLK_CFG);
578 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000579}
580
Jassi Brar230d42d2009-11-30 07:39:42 +0000581#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
582
583static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
584 struct spi_message *msg)
585{
586 struct device *dev = &sdd->pdev->dev;
587 struct spi_transfer *xfer;
588
589 if (msg->is_dma_mapped)
590 return 0;
591
592 /* First mark all xfer unmapped */
593 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
594 xfer->rx_dma = XFER_DMAADDR_INVALID;
595 xfer->tx_dma = XFER_DMAADDR_INVALID;
596 }
597
598 /* Map until end or first fail */
599 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
600
Thomas Abrahama5238e32012-07-13 07:15:14 +0900601 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
Jassi Brare02ddd42010-09-29 17:31:31 +0900602 continue;
603
Jassi Brar230d42d2009-11-30 07:39:42 +0000604 if (xfer->tx_buf != NULL) {
Jassi Brar251ee472010-09-03 10:36:26 +0900605 xfer->tx_dma = dma_map_single(dev,
606 (void *)xfer->tx_buf, xfer->len,
607 DMA_TO_DEVICE);
Jassi Brar230d42d2009-11-30 07:39:42 +0000608 if (dma_mapping_error(dev, xfer->tx_dma)) {
609 dev_err(dev, "dma_map_single Tx failed\n");
610 xfer->tx_dma = XFER_DMAADDR_INVALID;
611 return -ENOMEM;
612 }
613 }
614
615 if (xfer->rx_buf != NULL) {
616 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
617 xfer->len, DMA_FROM_DEVICE);
618 if (dma_mapping_error(dev, xfer->rx_dma)) {
619 dev_err(dev, "dma_map_single Rx failed\n");
620 dma_unmap_single(dev, xfer->tx_dma,
621 xfer->len, DMA_TO_DEVICE);
622 xfer->tx_dma = XFER_DMAADDR_INVALID;
623 xfer->rx_dma = XFER_DMAADDR_INVALID;
624 return -ENOMEM;
625 }
626 }
627 }
628
629 return 0;
630}
631
632static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
633 struct spi_message *msg)
634{
635 struct device *dev = &sdd->pdev->dev;
636 struct spi_transfer *xfer;
637
638 if (msg->is_dma_mapped)
639 return;
640
641 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
642
Thomas Abrahama5238e32012-07-13 07:15:14 +0900643 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
Jassi Brare02ddd42010-09-29 17:31:31 +0900644 continue;
645
Jassi Brar230d42d2009-11-30 07:39:42 +0000646 if (xfer->rx_buf != NULL
647 && xfer->rx_dma != XFER_DMAADDR_INVALID)
648 dma_unmap_single(dev, xfer->rx_dma,
649 xfer->len, DMA_FROM_DEVICE);
650
651 if (xfer->tx_buf != NULL
652 && xfer->tx_dma != XFER_DMAADDR_INVALID)
653 dma_unmap_single(dev, xfer->tx_dma,
654 xfer->len, DMA_TO_DEVICE);
655 }
656}
657
Mark Brownad2a99a2012-02-15 14:48:32 -0800658static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
659 struct spi_message *msg)
Jassi Brar230d42d2009-11-30 07:39:42 +0000660{
Mark Brownad2a99a2012-02-15 14:48:32 -0800661 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
Jassi Brar230d42d2009-11-30 07:39:42 +0000662 struct spi_device *spi = msg->spi;
663 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
664 struct spi_transfer *xfer;
665 int status = 0, cs_toggle = 0;
666 u32 speed;
667 u8 bpw;
668
669 /* If Master's(controller) state differs from that needed by Slave */
670 if (sdd->cur_speed != spi->max_speed_hz
671 || sdd->cur_mode != spi->mode
672 || sdd->cur_bpw != spi->bits_per_word) {
673 sdd->cur_bpw = spi->bits_per_word;
674 sdd->cur_speed = spi->max_speed_hz;
675 sdd->cur_mode = spi->mode;
676 s3c64xx_spi_config(sdd);
677 }
678
679 /* Map all the transfers if needed */
680 if (s3c64xx_spi_map_mssg(sdd, msg)) {
681 dev_err(&spi->dev,
682 "Xfer: Unable to map message buffers!\n");
683 status = -ENOMEM;
684 goto out;
685 }
686
687 /* Configure feedback delay */
688 writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
689
690 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
691
692 unsigned long flags;
693 int use_dma;
694
695 INIT_COMPLETION(sdd->xfer_completion);
696
697 /* Only BPW and Speed may change across transfers */
698 bpw = xfer->bits_per_word ? : spi->bits_per_word;
699 speed = xfer->speed_hz ? : spi->max_speed_hz;
700
Jassi Brar0c92ecf2010-09-29 17:31:33 +0900701 if (xfer->len % (bpw / 8)) {
702 dev_err(&spi->dev,
703 "Xfer length(%u) not a multiple of word size(%u)\n",
704 xfer->len, bpw / 8);
705 status = -EIO;
706 goto out;
707 }
708
Jassi Brar230d42d2009-11-30 07:39:42 +0000709 if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
710 sdd->cur_bpw = bpw;
711 sdd->cur_speed = speed;
712 s3c64xx_spi_config(sdd);
713 }
714
715 /* Polling method for xfers not bigger than FIFO capacity */
Thomas Abrahama5238e32012-07-13 07:15:14 +0900716 if (xfer->len <= ((FIFO_LVL_MASK(sdd) >> 1) + 1))
Jassi Brar230d42d2009-11-30 07:39:42 +0000717 use_dma = 0;
718 else
719 use_dma = 1;
720
721 spin_lock_irqsave(&sdd->lock, flags);
722
723 /* Pending only which is to be done */
724 sdd->state &= ~RXBUSY;
725 sdd->state &= ~TXBUSY;
726
727 enable_datapath(sdd, spi, xfer, use_dma);
728
729 /* Slave Select */
730 enable_cs(sdd, spi);
731
732 /* Start the signals */
733 S3C64XX_SPI_ACT(sdd);
734
735 spin_unlock_irqrestore(&sdd->lock, flags);
736
737 status = wait_for_xfer(sdd, xfer, use_dma);
738
739 /* Quiese the signals */
740 S3C64XX_SPI_DEACT(sdd);
741
742 if (status) {
Joe Perches8a349d42010-02-02 07:22:13 +0000743 dev_err(&spi->dev, "I/O Error: "
744 "rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
Jassi Brar230d42d2009-11-30 07:39:42 +0000745 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
746 (sdd->state & RXBUSY) ? 'f' : 'p',
747 (sdd->state & TXBUSY) ? 'f' : 'p',
748 xfer->len);
749
750 if (use_dma) {
751 if (xfer->tx_buf != NULL
752 && (sdd->state & TXBUSY))
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900753 sdd->ops->stop(sdd->tx_dma.ch);
Jassi Brar230d42d2009-11-30 07:39:42 +0000754 if (xfer->rx_buf != NULL
755 && (sdd->state & RXBUSY))
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900756 sdd->ops->stop(sdd->rx_dma.ch);
Jassi Brar230d42d2009-11-30 07:39:42 +0000757 }
758
759 goto out;
760 }
761
762 if (xfer->delay_usecs)
763 udelay(xfer->delay_usecs);
764
765 if (xfer->cs_change) {
766 /* Hint that the next mssg is gonna be
767 for the same device */
768 if (list_is_last(&xfer->transfer_list,
769 &msg->transfers))
770 cs_toggle = 1;
771 else
772 disable_cs(sdd, spi);
773 }
774
775 msg->actual_length += xfer->len;
776
777 flush_fifo(sdd);
778 }
779
780out:
781 if (!cs_toggle || status)
782 disable_cs(sdd, spi);
783 else
784 sdd->tgl_spi = spi;
785
786 s3c64xx_spi_unmap_mssg(sdd, msg);
787
788 msg->status = status;
789
Mark Brownad2a99a2012-02-15 14:48:32 -0800790 spi_finalize_current_message(master);
791
792 return 0;
Jassi Brar230d42d2009-11-30 07:39:42 +0000793}
794
Mark Brownad2a99a2012-02-15 14:48:32 -0800795static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
Jassi Brar230d42d2009-11-30 07:39:42 +0000796{
Mark Brownad2a99a2012-02-15 14:48:32 -0800797 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
Jassi Brar230d42d2009-11-30 07:39:42 +0000798
799 /* Acquire DMA channels */
800 while (!acquire_dma(sdd))
801 msleep(10);
802
Mark Brownb97b6622011-12-04 00:58:06 +0000803 pm_runtime_get_sync(&sdd->pdev->dev);
804
Mark Brownad2a99a2012-02-15 14:48:32 -0800805 return 0;
806}
Jassi Brar230d42d2009-11-30 07:39:42 +0000807
Mark Brownad2a99a2012-02-15 14:48:32 -0800808static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
809{
810 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
Jassi Brar230d42d2009-11-30 07:39:42 +0000811
812 /* Free DMA channels */
Boojin Kim82ab8cd2011-09-02 09:44:42 +0900813 sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
814 sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
Mark Brownb97b6622011-12-04 00:58:06 +0000815
816 pm_runtime_put(&sdd->pdev->dev);
Jassi Brar230d42d2009-11-30 07:39:42 +0000817
818 return 0;
819}
820
821/*
822 * Here we only check the validity of requested configuration
823 * and save the configuration in a local data-structure.
824 * The controller is actually configured only just before we
825 * get a message to transfer.
826 */
827static int s3c64xx_spi_setup(struct spi_device *spi)
828{
829 struct s3c64xx_spi_csinfo *cs = spi->controller_data;
830 struct s3c64xx_spi_driver_data *sdd;
Jassi Brarad7de722010-01-20 13:49:44 -0700831 struct s3c64xx_spi_info *sci;
Jassi Brar230d42d2009-11-30 07:39:42 +0000832 struct spi_message *msg;
Jassi Brar230d42d2009-11-30 07:39:42 +0000833 unsigned long flags;
834 int err = 0;
835
836 if (cs == NULL || cs->set_level == NULL) {
837 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
838 return -ENODEV;
839 }
840
841 sdd = spi_master_get_devdata(spi->master);
842 sci = sdd->cntrlr_info;
843
844 spin_lock_irqsave(&sdd->lock, flags);
845
846 list_for_each_entry(msg, &sdd->queue, queue) {
847 /* Is some mssg is already queued for this device */
848 if (msg->spi == spi) {
849 dev_err(&spi->dev,
850 "setup: attempt while mssg in queue!\n");
851 spin_unlock_irqrestore(&sdd->lock, flags);
852 return -EBUSY;
853 }
854 }
855
Jassi Brar230d42d2009-11-30 07:39:42 +0000856 spin_unlock_irqrestore(&sdd->lock, flags);
857
858 if (spi->bits_per_word != 8
859 && spi->bits_per_word != 16
860 && spi->bits_per_word != 32) {
861 dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
862 spi->bits_per_word);
863 err = -EINVAL;
864 goto setup_exit;
865 }
866
Mark Brownb97b6622011-12-04 00:58:06 +0000867 pm_runtime_get_sync(&sdd->pdev->dev);
868
Jassi Brar230d42d2009-11-30 07:39:42 +0000869 /* Check if we can provide the requested rate */
Thomas Abrahama5238e32012-07-13 07:15:14 +0900870 if (!sdd->port_conf->clk_from_cmu) {
Jassi Brarb42a81c2010-09-29 17:31:33 +0900871 u32 psr, speed;
Jassi Brar230d42d2009-11-30 07:39:42 +0000872
Jassi Brarb42a81c2010-09-29 17:31:33 +0900873 /* Max possible */
874 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
Jassi Brar230d42d2009-11-30 07:39:42 +0000875
Jassi Brarb42a81c2010-09-29 17:31:33 +0900876 if (spi->max_speed_hz > speed)
877 spi->max_speed_hz = speed;
Jassi Brar230d42d2009-11-30 07:39:42 +0000878
Jassi Brarb42a81c2010-09-29 17:31:33 +0900879 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
880 psr &= S3C64XX_SPI_PSR_MASK;
881 if (psr == S3C64XX_SPI_PSR_MASK)
882 psr--;
883
884 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
885 if (spi->max_speed_hz < speed) {
886 if (psr+1 < S3C64XX_SPI_PSR_MASK) {
887 psr++;
888 } else {
889 err = -EINVAL;
890 goto setup_exit;
891 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000892 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000893
Jassi Brarb42a81c2010-09-29 17:31:33 +0900894 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
895 if (spi->max_speed_hz >= speed)
896 spi->max_speed_hz = speed;
897 else
898 err = -EINVAL;
899 }
Jassi Brar230d42d2009-11-30 07:39:42 +0000900
Mark Brownb97b6622011-12-04 00:58:06 +0000901 pm_runtime_put(&sdd->pdev->dev);
902
Jassi Brar230d42d2009-11-30 07:39:42 +0000903setup_exit:
904
905 /* setup() returns with device de-selected */
906 disable_cs(sdd, spi);
907
908 return err;
909}
910
Mark Brownc2573122011-11-10 10:57:32 +0000911static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
912{
913 struct s3c64xx_spi_driver_data *sdd = data;
914 struct spi_master *spi = sdd->master;
915 unsigned int val;
916
917 val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
918
919 val &= S3C64XX_SPI_PND_RX_OVERRUN_CLR |
920 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
921 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
922 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
923
924 writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
925
926 if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
927 dev_err(&spi->dev, "RX overrun\n");
928 if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
929 dev_err(&spi->dev, "RX underrun\n");
930 if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
931 dev_err(&spi->dev, "TX overrun\n");
932 if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
933 dev_err(&spi->dev, "TX underrun\n");
934
935 return IRQ_HANDLED;
936}
937
Jassi Brar230d42d2009-11-30 07:39:42 +0000938static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
939{
Jassi Brarad7de722010-01-20 13:49:44 -0700940 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
Jassi Brar230d42d2009-11-30 07:39:42 +0000941 void __iomem *regs = sdd->regs;
942 unsigned int val;
943
944 sdd->cur_speed = 0;
945
946 S3C64XX_SPI_DEACT(sdd);
947
948 /* Disable Interrupts - we use Polling if not DMA mode */
949 writel(0, regs + S3C64XX_SPI_INT_EN);
950
Thomas Abrahama5238e32012-07-13 07:15:14 +0900951 if (!sdd->port_conf->clk_from_cmu)
Jassi Brarb42a81c2010-09-29 17:31:33 +0900952 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
Jassi Brar230d42d2009-11-30 07:39:42 +0000953 regs + S3C64XX_SPI_CLK_CFG);
954 writel(0, regs + S3C64XX_SPI_MODE_CFG);
955 writel(0, regs + S3C64XX_SPI_PACKET_CNT);
956
957 /* Clear any irq pending bits */
958 writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
959 regs + S3C64XX_SPI_PENDING_CLR);
960
961 writel(0, regs + S3C64XX_SPI_SWAP_CFG);
962
963 val = readl(regs + S3C64XX_SPI_MODE_CFG);
964 val &= ~S3C64XX_SPI_MODE_4BURST;
965 val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
966 val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
967 writel(val, regs + S3C64XX_SPI_MODE_CFG);
968
969 flush_fifo(sdd);
970}
971
Thomas Abrahama5238e32012-07-13 07:15:14 +0900972static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
973 struct platform_device *pdev)
974{
975 return (struct s3c64xx_spi_port_config *)
976 platform_get_device_id(pdev)->driver_data;
977}
978
Jassi Brar230d42d2009-11-30 07:39:42 +0000979static int __init s3c64xx_spi_probe(struct platform_device *pdev)
980{
981 struct resource *mem_res, *dmatx_res, *dmarx_res;
982 struct s3c64xx_spi_driver_data *sdd;
Jassi Brarad7de722010-01-20 13:49:44 -0700983 struct s3c64xx_spi_info *sci;
Jassi Brar230d42d2009-11-30 07:39:42 +0000984 struct spi_master *master;
Mark Brownc2573122011-11-10 10:57:32 +0000985 int ret, irq;
Padmavathi Vennaa24d8502011-11-02 20:04:19 +0900986 char clk_name[16];
Jassi Brar230d42d2009-11-30 07:39:42 +0000987
988 if (pdev->id < 0) {
989 dev_err(&pdev->dev,
990 "Invalid platform device id-%d\n", pdev->id);
991 return -ENODEV;
992 }
993
994 if (pdev->dev.platform_data == NULL) {
995 dev_err(&pdev->dev, "platform_data missing!\n");
996 return -ENODEV;
997 }
998
Mark Browncc0fc0b2010-09-01 08:55:22 -0600999 sci = pdev->dev.platform_data;
Mark Browncc0fc0b2010-09-01 08:55:22 -06001000
Jassi Brar230d42d2009-11-30 07:39:42 +00001001 /* Check for availability of necessary resource */
1002
1003 dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1004 if (dmatx_res == NULL) {
1005 dev_err(&pdev->dev, "Unable to get SPI-Tx dma resource\n");
1006 return -ENXIO;
1007 }
1008
1009 dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1010 if (dmarx_res == NULL) {
1011 dev_err(&pdev->dev, "Unable to get SPI-Rx dma resource\n");
1012 return -ENXIO;
1013 }
1014
1015 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1016 if (mem_res == NULL) {
1017 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1018 return -ENXIO;
1019 }
1020
Mark Brownc2573122011-11-10 10:57:32 +00001021 irq = platform_get_irq(pdev, 0);
1022 if (irq < 0) {
1023 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1024 return irq;
1025 }
1026
Jassi Brar230d42d2009-11-30 07:39:42 +00001027 master = spi_alloc_master(&pdev->dev,
1028 sizeof(struct s3c64xx_spi_driver_data));
1029 if (master == NULL) {
1030 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1031 return -ENOMEM;
1032 }
1033
Jassi Brar230d42d2009-11-30 07:39:42 +00001034 platform_set_drvdata(pdev, master);
1035
1036 sdd = spi_master_get_devdata(master);
Thomas Abrahama5238e32012-07-13 07:15:14 +09001037 sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
Jassi Brar230d42d2009-11-30 07:39:42 +00001038 sdd->master = master;
1039 sdd->cntrlr_info = sci;
1040 sdd->pdev = pdev;
1041 sdd->sfr_start = mem_res->start;
Boojin Kim82ab8cd2011-09-02 09:44:42 +09001042 sdd->tx_dma.dmach = dmatx_res->start;
Kyoungil Kim054ebcc2012-03-10 09:48:46 +09001043 sdd->tx_dma.direction = DMA_MEM_TO_DEV;
Boojin Kim82ab8cd2011-09-02 09:44:42 +09001044 sdd->rx_dma.dmach = dmarx_res->start;
Kyoungil Kim054ebcc2012-03-10 09:48:46 +09001045 sdd->rx_dma.direction = DMA_DEV_TO_MEM;
Thomas Abrahama5238e32012-07-13 07:15:14 +09001046 sdd->port_id = pdev->id;
Jassi Brar230d42d2009-11-30 07:39:42 +00001047
1048 sdd->cur_bpw = 8;
1049
Thomas Abrahama5238e32012-07-13 07:15:14 +09001050 master->bus_num = sdd->port_id;
Jassi Brar230d42d2009-11-30 07:39:42 +00001051 master->setup = s3c64xx_spi_setup;
Mark Brownad2a99a2012-02-15 14:48:32 -08001052 master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1053 master->transfer_one_message = s3c64xx_spi_transfer_one_message;
1054 master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
Jassi Brar230d42d2009-11-30 07:39:42 +00001055 master->num_chipselect = sci->num_cs;
1056 master->dma_alignment = 8;
1057 /* the spi->mode bits understood by this driver: */
1058 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1059
1060 if (request_mem_region(mem_res->start,
1061 resource_size(mem_res), pdev->name) == NULL) {
1062 dev_err(&pdev->dev, "Req mem region failed\n");
1063 ret = -ENXIO;
1064 goto err0;
1065 }
1066
1067 sdd->regs = ioremap(mem_res->start, resource_size(mem_res));
1068 if (sdd->regs == NULL) {
1069 dev_err(&pdev->dev, "Unable to remap IO\n");
1070 ret = -ENXIO;
1071 goto err1;
1072 }
1073
1074 if (sci->cfg_gpio == NULL || sci->cfg_gpio(pdev)) {
1075 dev_err(&pdev->dev, "Unable to config gpio\n");
1076 ret = -EBUSY;
1077 goto err2;
1078 }
1079
1080 /* Setup clocks */
1081 sdd->clk = clk_get(&pdev->dev, "spi");
1082 if (IS_ERR(sdd->clk)) {
1083 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1084 ret = PTR_ERR(sdd->clk);
1085 goto err3;
1086 }
1087
1088 if (clk_enable(sdd->clk)) {
1089 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1090 ret = -EBUSY;
1091 goto err4;
1092 }
1093
Padmavathi Vennaa24d8502011-11-02 20:04:19 +09001094 sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1095 sdd->src_clk = clk_get(&pdev->dev, clk_name);
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001096 if (IS_ERR(sdd->src_clk)) {
Jassi Brar230d42d2009-11-30 07:39:42 +00001097 dev_err(&pdev->dev,
Padmavathi Vennaa24d8502011-11-02 20:04:19 +09001098 "Unable to acquire clock '%s'\n", clk_name);
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001099 ret = PTR_ERR(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001100 goto err5;
1101 }
1102
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001103 if (clk_enable(sdd->src_clk)) {
Padmavathi Vennaa24d8502011-11-02 20:04:19 +09001104 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
Jassi Brar230d42d2009-11-30 07:39:42 +00001105 ret = -EBUSY;
1106 goto err6;
1107 }
1108
Jassi Brar230d42d2009-11-30 07:39:42 +00001109 /* Setup Deufult Mode */
Thomas Abrahama5238e32012-07-13 07:15:14 +09001110 s3c64xx_spi_hwinit(sdd, sdd->port_id);
Jassi Brar230d42d2009-11-30 07:39:42 +00001111
1112 spin_lock_init(&sdd->lock);
1113 init_completion(&sdd->xfer_completion);
Jassi Brar230d42d2009-11-30 07:39:42 +00001114 INIT_LIST_HEAD(&sdd->queue);
1115
Mark Brownc2573122011-11-10 10:57:32 +00001116 ret = request_irq(irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd);
1117 if (ret != 0) {
1118 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1119 irq, ret);
Mark Brownad2a99a2012-02-15 14:48:32 -08001120 goto err7;
Mark Brownc2573122011-11-10 10:57:32 +00001121 }
1122
1123 writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1124 S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1125 sdd->regs + S3C64XX_SPI_INT_EN);
1126
Jassi Brar230d42d2009-11-30 07:39:42 +00001127 if (spi_register_master(master)) {
1128 dev_err(&pdev->dev, "cannot register SPI master\n");
1129 ret = -EBUSY;
Mark Brownad2a99a2012-02-15 14:48:32 -08001130 goto err8;
Jassi Brar230d42d2009-11-30 07:39:42 +00001131 }
1132
Joe Perches8a349d42010-02-02 07:22:13 +00001133 dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
1134 "with %d Slaves attached\n",
Thomas Abrahama5238e32012-07-13 07:15:14 +09001135 sdd->port_id, master->num_chipselect);
Joe Perches8a349d42010-02-02 07:22:13 +00001136 dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\tDMA=[Rx-%d, Tx-%d]\n",
Jassi Brar230d42d2009-11-30 07:39:42 +00001137 mem_res->end, mem_res->start,
Boojin Kim82ab8cd2011-09-02 09:44:42 +09001138 sdd->rx_dma.dmach, sdd->tx_dma.dmach);
Jassi Brar230d42d2009-11-30 07:39:42 +00001139
Mark Brownb97b6622011-12-04 00:58:06 +00001140 pm_runtime_enable(&pdev->dev);
1141
Jassi Brar230d42d2009-11-30 07:39:42 +00001142 return 0;
1143
1144err8:
Mark Brownad2a99a2012-02-15 14:48:32 -08001145 free_irq(irq, sdd);
Jassi Brar230d42d2009-11-30 07:39:42 +00001146err7:
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001147 clk_disable(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001148err6:
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001149 clk_put(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001150err5:
1151 clk_disable(sdd->clk);
1152err4:
1153 clk_put(sdd->clk);
1154err3:
1155err2:
1156 iounmap((void *) sdd->regs);
1157err1:
1158 release_mem_region(mem_res->start, resource_size(mem_res));
1159err0:
1160 platform_set_drvdata(pdev, NULL);
1161 spi_master_put(master);
1162
1163 return ret;
1164}
1165
1166static int s3c64xx_spi_remove(struct platform_device *pdev)
1167{
1168 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1169 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
Jassi Brar230d42d2009-11-30 07:39:42 +00001170 struct resource *mem_res;
Jassi Brar230d42d2009-11-30 07:39:42 +00001171
Mark Brownb97b6622011-12-04 00:58:06 +00001172 pm_runtime_disable(&pdev->dev);
1173
Jassi Brar230d42d2009-11-30 07:39:42 +00001174 spi_unregister_master(master);
1175
Mark Brownc2573122011-11-10 10:57:32 +00001176 writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1177
1178 free_irq(platform_get_irq(pdev, 0), sdd);
1179
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001180 clk_disable(sdd->src_clk);
1181 clk_put(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001182
1183 clk_disable(sdd->clk);
1184 clk_put(sdd->clk);
1185
1186 iounmap((void *) sdd->regs);
1187
1188 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
Jassi Braref6c6802010-01-20 13:49:44 -07001189 if (mem_res != NULL)
1190 release_mem_region(mem_res->start, resource_size(mem_res));
Jassi Brar230d42d2009-11-30 07:39:42 +00001191
1192 platform_set_drvdata(pdev, NULL);
1193 spi_master_put(master);
1194
1195 return 0;
1196}
1197
1198#ifdef CONFIG_PM
Mark Browne25d0bf2011-12-04 00:36:18 +00001199static int s3c64xx_spi_suspend(struct device *dev)
Jassi Brar230d42d2009-11-30 07:39:42 +00001200{
Mark Browne25d0bf2011-12-04 00:36:18 +00001201 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
Jassi Brar230d42d2009-11-30 07:39:42 +00001202 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
Jassi Brar230d42d2009-11-30 07:39:42 +00001203
Mark Brownad2a99a2012-02-15 14:48:32 -08001204 spi_master_suspend(master);
Jassi Brar230d42d2009-11-30 07:39:42 +00001205
1206 /* Disable the clock */
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001207 clk_disable(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001208 clk_disable(sdd->clk);
1209
1210 sdd->cur_speed = 0; /* Output Clock is stopped */
1211
1212 return 0;
1213}
1214
Mark Browne25d0bf2011-12-04 00:36:18 +00001215static int s3c64xx_spi_resume(struct device *dev)
Jassi Brar230d42d2009-11-30 07:39:42 +00001216{
Mark Browne25d0bf2011-12-04 00:36:18 +00001217 struct platform_device *pdev = to_platform_device(dev);
1218 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
Jassi Brar230d42d2009-11-30 07:39:42 +00001219 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
Jassi Brarad7de722010-01-20 13:49:44 -07001220 struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
Jassi Brar230d42d2009-11-30 07:39:42 +00001221
1222 sci->cfg_gpio(pdev);
1223
1224 /* Enable the clock */
Jassi Brarb0d5d6e2010-01-20 13:49:44 -07001225 clk_enable(sdd->src_clk);
Jassi Brar230d42d2009-11-30 07:39:42 +00001226 clk_enable(sdd->clk);
1227
Thomas Abrahama5238e32012-07-13 07:15:14 +09001228 s3c64xx_spi_hwinit(sdd, sdd->port_id);
Jassi Brar230d42d2009-11-30 07:39:42 +00001229
Mark Brownad2a99a2012-02-15 14:48:32 -08001230 spi_master_resume(master);
Jassi Brar230d42d2009-11-30 07:39:42 +00001231
1232 return 0;
1233}
Jassi Brar230d42d2009-11-30 07:39:42 +00001234#endif /* CONFIG_PM */
1235
Mark Brownb97b6622011-12-04 00:58:06 +00001236#ifdef CONFIG_PM_RUNTIME
1237static int s3c64xx_spi_runtime_suspend(struct device *dev)
1238{
1239 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1240 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1241
1242 clk_disable(sdd->clk);
1243 clk_disable(sdd->src_clk);
1244
1245 return 0;
1246}
1247
1248static int s3c64xx_spi_runtime_resume(struct device *dev)
1249{
1250 struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
1251 struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1252
1253 clk_enable(sdd->src_clk);
1254 clk_enable(sdd->clk);
1255
1256 return 0;
1257}
1258#endif /* CONFIG_PM_RUNTIME */
1259
Mark Browne25d0bf2011-12-04 00:36:18 +00001260static const struct dev_pm_ops s3c64xx_spi_pm = {
1261 SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
Mark Brownb97b6622011-12-04 00:58:06 +00001262 SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1263 s3c64xx_spi_runtime_resume, NULL)
Mark Browne25d0bf2011-12-04 00:36:18 +00001264};
1265
Thomas Abrahama5238e32012-07-13 07:15:14 +09001266struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1267 .fifo_lvl_mask = { 0x7f },
1268 .rx_lvl_offset = 13,
1269 .tx_st_done = 21,
1270 .high_speed = true,
1271};
1272
1273struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1274 .fifo_lvl_mask = { 0x7f, 0x7F },
1275 .rx_lvl_offset = 13,
1276 .tx_st_done = 21,
1277};
1278
1279struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1280 .fifo_lvl_mask = { 0x1ff, 0x7F },
1281 .rx_lvl_offset = 15,
1282 .tx_st_done = 25,
1283};
1284
1285struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1286 .fifo_lvl_mask = { 0x7f, 0x7F },
1287 .rx_lvl_offset = 13,
1288 .tx_st_done = 21,
1289 .high_speed = true,
1290};
1291
1292struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1293 .fifo_lvl_mask = { 0x1ff, 0x7F },
1294 .rx_lvl_offset = 15,
1295 .tx_st_done = 25,
1296 .high_speed = true,
1297};
1298
1299struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1300 .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
1301 .rx_lvl_offset = 15,
1302 .tx_st_done = 25,
1303 .high_speed = true,
1304 .clk_from_cmu = true,
1305};
1306
1307static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1308 {
1309 .name = "s3c2443-spi",
1310 .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config,
1311 }, {
1312 .name = "s3c6410-spi",
1313 .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config,
1314 }, {
1315 .name = "s5p64x0-spi",
1316 .driver_data = (kernel_ulong_t)&s5p64x0_spi_port_config,
1317 }, {
1318 .name = "s5pc100-spi",
1319 .driver_data = (kernel_ulong_t)&s5pc100_spi_port_config,
1320 }, {
1321 .name = "s5pv210-spi",
1322 .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config,
1323 }, {
1324 .name = "exynos4210-spi",
1325 .driver_data = (kernel_ulong_t)&exynos4_spi_port_config,
1326 },
1327 { },
1328};
1329
Jassi Brar230d42d2009-11-30 07:39:42 +00001330static struct platform_driver s3c64xx_spi_driver = {
1331 .driver = {
1332 .name = "s3c64xx-spi",
1333 .owner = THIS_MODULE,
Mark Browne25d0bf2011-12-04 00:36:18 +00001334 .pm = &s3c64xx_spi_pm,
Jassi Brar230d42d2009-11-30 07:39:42 +00001335 },
1336 .remove = s3c64xx_spi_remove,
Thomas Abrahama5238e32012-07-13 07:15:14 +09001337 .id_table = s3c64xx_spi_driver_ids,
Jassi Brar230d42d2009-11-30 07:39:42 +00001338};
1339MODULE_ALIAS("platform:s3c64xx-spi");
1340
1341static int __init s3c64xx_spi_init(void)
1342{
1343 return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
1344}
Mark Brownd2a787f2010-09-07 11:29:17 +01001345subsys_initcall(s3c64xx_spi_init);
Jassi Brar230d42d2009-11-30 07:39:42 +00001346
1347static void __exit s3c64xx_spi_exit(void)
1348{
1349 platform_driver_unregister(&s3c64xx_spi_driver);
1350}
1351module_exit(s3c64xx_spi_exit);
1352
1353MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1354MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1355MODULE_LICENSE("GPL");