Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Freescale STMP37XX/STMP378X Application UART driver |
| 3 | * |
| 4 | * Author: dmitry pervushin <dimka@embeddedalley.com> |
| 5 | * |
| 6 | * Copyright 2008-2010 Freescale Semiconductor, Inc. |
| 7 | * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. |
| 8 | * |
| 9 | * The code contained herein is licensed under the GNU General Public |
| 10 | * License. You may obtain a copy of the GNU General Public License |
| 11 | * Version 2 or later at the following locations: |
| 12 | * |
| 13 | * http://www.opensource.org/licenses/gpl-license.html |
| 14 | * http://www.gnu.org/copyleft/gpl.html |
| 15 | */ |
| 16 | |
| 17 | #include <linux/kernel.h> |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 18 | #include <linux/errno.h> |
| 19 | #include <linux/init.h> |
| 20 | #include <linux/console.h> |
| 21 | #include <linux/interrupt.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/wait.h> |
| 25 | #include <linux/tty.h> |
| 26 | #include <linux/tty_driver.h> |
| 27 | #include <linux/tty_flip.h> |
| 28 | #include <linux/serial.h> |
| 29 | #include <linux/serial_core.h> |
| 30 | #include <linux/platform_device.h> |
| 31 | #include <linux/device.h> |
| 32 | #include <linux/clk.h> |
| 33 | #include <linux/delay.h> |
| 34 | #include <linux/io.h> |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 35 | #include <linux/of_device.h> |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 36 | #include <linux/dma-mapping.h> |
Shawn Guo | bcc20f9 | 2013-02-26 13:47:41 +0800 | [diff] [blame] | 37 | #include <linux/dmaengine.h> |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 38 | |
| 39 | #include <asm/cacheflush.h> |
| 40 | |
| 41 | #define MXS_AUART_PORTS 5 |
Hector Palacios | 9987f76 | 2013-10-03 09:32:03 +0200 | [diff] [blame] | 42 | #define MXS_AUART_FIFO_SIZE 16 |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 43 | |
| 44 | #define AUART_CTRL0 0x00000000 |
| 45 | #define AUART_CTRL0_SET 0x00000004 |
| 46 | #define AUART_CTRL0_CLR 0x00000008 |
| 47 | #define AUART_CTRL0_TOG 0x0000000c |
| 48 | #define AUART_CTRL1 0x00000010 |
| 49 | #define AUART_CTRL1_SET 0x00000014 |
| 50 | #define AUART_CTRL1_CLR 0x00000018 |
| 51 | #define AUART_CTRL1_TOG 0x0000001c |
| 52 | #define AUART_CTRL2 0x00000020 |
| 53 | #define AUART_CTRL2_SET 0x00000024 |
| 54 | #define AUART_CTRL2_CLR 0x00000028 |
| 55 | #define AUART_CTRL2_TOG 0x0000002c |
| 56 | #define AUART_LINECTRL 0x00000030 |
| 57 | #define AUART_LINECTRL_SET 0x00000034 |
| 58 | #define AUART_LINECTRL_CLR 0x00000038 |
| 59 | #define AUART_LINECTRL_TOG 0x0000003c |
| 60 | #define AUART_LINECTRL2 0x00000040 |
| 61 | #define AUART_LINECTRL2_SET 0x00000044 |
| 62 | #define AUART_LINECTRL2_CLR 0x00000048 |
| 63 | #define AUART_LINECTRL2_TOG 0x0000004c |
| 64 | #define AUART_INTR 0x00000050 |
| 65 | #define AUART_INTR_SET 0x00000054 |
| 66 | #define AUART_INTR_CLR 0x00000058 |
| 67 | #define AUART_INTR_TOG 0x0000005c |
| 68 | #define AUART_DATA 0x00000060 |
| 69 | #define AUART_STAT 0x00000070 |
| 70 | #define AUART_DEBUG 0x00000080 |
| 71 | #define AUART_VERSION 0x00000090 |
| 72 | #define AUART_AUTOBAUD 0x000000a0 |
| 73 | |
| 74 | #define AUART_CTRL0_SFTRST (1 << 31) |
| 75 | #define AUART_CTRL0_CLKGATE (1 << 30) |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 76 | #define AUART_CTRL0_RXTO_ENABLE (1 << 27) |
| 77 | #define AUART_CTRL0_RXTIMEOUT(v) (((v) & 0x7ff) << 16) |
| 78 | #define AUART_CTRL0_XFER_COUNT(v) ((v) & 0xffff) |
| 79 | |
| 80 | #define AUART_CTRL1_XFER_COUNT(v) ((v) & 0xffff) |
| 81 | |
| 82 | #define AUART_CTRL2_DMAONERR (1 << 26) |
| 83 | #define AUART_CTRL2_TXDMAE (1 << 25) |
| 84 | #define AUART_CTRL2_RXDMAE (1 << 24) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 85 | |
| 86 | #define AUART_CTRL2_CTSEN (1 << 15) |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 87 | #define AUART_CTRL2_RTSEN (1 << 14) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 88 | #define AUART_CTRL2_RTS (1 << 11) |
| 89 | #define AUART_CTRL2_RXE (1 << 9) |
| 90 | #define AUART_CTRL2_TXE (1 << 8) |
| 91 | #define AUART_CTRL2_UARTEN (1 << 0) |
| 92 | |
| 93 | #define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16 |
| 94 | #define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000 |
| 95 | #define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16) |
| 96 | #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT 8 |
| 97 | #define AUART_LINECTRL_BAUD_DIVFRAC_MASK 0x00003f00 |
| 98 | #define AUART_LINECTRL_BAUD_DIVFRAC(v) (((v) & 0x3f) << 8) |
| 99 | #define AUART_LINECTRL_WLEN_MASK 0x00000060 |
| 100 | #define AUART_LINECTRL_WLEN(v) (((v) & 0x3) << 5) |
| 101 | #define AUART_LINECTRL_FEN (1 << 4) |
| 102 | #define AUART_LINECTRL_STP2 (1 << 3) |
| 103 | #define AUART_LINECTRL_EPS (1 << 2) |
| 104 | #define AUART_LINECTRL_PEN (1 << 1) |
| 105 | #define AUART_LINECTRL_BRK (1 << 0) |
| 106 | |
| 107 | #define AUART_INTR_RTIEN (1 << 22) |
| 108 | #define AUART_INTR_TXIEN (1 << 21) |
| 109 | #define AUART_INTR_RXIEN (1 << 20) |
| 110 | #define AUART_INTR_CTSMIEN (1 << 17) |
| 111 | #define AUART_INTR_RTIS (1 << 6) |
| 112 | #define AUART_INTR_TXIS (1 << 5) |
| 113 | #define AUART_INTR_RXIS (1 << 4) |
| 114 | #define AUART_INTR_CTSMIS (1 << 1) |
| 115 | |
| 116 | #define AUART_STAT_BUSY (1 << 29) |
| 117 | #define AUART_STAT_CTS (1 << 28) |
| 118 | #define AUART_STAT_TXFE (1 << 27) |
| 119 | #define AUART_STAT_TXFF (1 << 25) |
| 120 | #define AUART_STAT_RXFE (1 << 24) |
| 121 | #define AUART_STAT_OERR (1 << 19) |
| 122 | #define AUART_STAT_BERR (1 << 18) |
| 123 | #define AUART_STAT_PERR (1 << 17) |
| 124 | #define AUART_STAT_FERR (1 << 16) |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 125 | #define AUART_STAT_RXCOUNT_MASK 0xffff |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 126 | |
| 127 | static struct uart_driver auart_driver; |
| 128 | |
Huang Shijie | f4b1f03b | 2012-11-16 16:03:52 +0800 | [diff] [blame] | 129 | enum mxs_auart_type { |
| 130 | IMX23_AUART, |
| 131 | IMX28_AUART, |
| 132 | }; |
| 133 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 134 | struct mxs_auart_port { |
| 135 | struct uart_port port; |
| 136 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 137 | #define MXS_AUART_DMA_ENABLED 0x2 |
| 138 | #define MXS_AUART_DMA_TX_SYNC 2 /* bit 2 */ |
| 139 | #define MXS_AUART_DMA_RX_READY 3 /* bit 3 */ |
Huang Shijie | 8418e67 | 2013-08-03 10:09:14 -0400 | [diff] [blame] | 140 | #define MXS_AUART_RTSCTS 4 /* bit 4 */ |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 141 | unsigned long flags; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 142 | unsigned int ctrl; |
Huang Shijie | f4b1f03b | 2012-11-16 16:03:52 +0800 | [diff] [blame] | 143 | enum mxs_auart_type devtype; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 144 | |
| 145 | unsigned int irq; |
| 146 | |
| 147 | struct clk *clk; |
| 148 | struct device *dev; |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 149 | |
| 150 | /* for DMA */ |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 151 | struct scatterlist tx_sgl; |
| 152 | struct dma_chan *tx_dma_chan; |
| 153 | void *tx_dma_buf; |
| 154 | |
| 155 | struct scatterlist rx_sgl; |
| 156 | struct dma_chan *rx_dma_chan; |
| 157 | void *rx_dma_buf; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 158 | }; |
| 159 | |
Huang Shijie | f4b1f03b | 2012-11-16 16:03:52 +0800 | [diff] [blame] | 160 | static struct platform_device_id mxs_auart_devtype[] = { |
| 161 | { .name = "mxs-auart-imx23", .driver_data = IMX23_AUART }, |
| 162 | { .name = "mxs-auart-imx28", .driver_data = IMX28_AUART }, |
| 163 | { /* sentinel */ } |
| 164 | }; |
| 165 | MODULE_DEVICE_TABLE(platform, mxs_auart_devtype); |
| 166 | |
| 167 | static struct of_device_id mxs_auart_dt_ids[] = { |
| 168 | { |
| 169 | .compatible = "fsl,imx28-auart", |
| 170 | .data = &mxs_auart_devtype[IMX28_AUART] |
| 171 | }, { |
| 172 | .compatible = "fsl,imx23-auart", |
| 173 | .data = &mxs_auart_devtype[IMX23_AUART] |
| 174 | }, { /* sentinel */ } |
| 175 | }; |
| 176 | MODULE_DEVICE_TABLE(of, mxs_auart_dt_ids); |
| 177 | |
| 178 | static inline int is_imx28_auart(struct mxs_auart_port *s) |
| 179 | { |
| 180 | return s->devtype == IMX28_AUART; |
| 181 | } |
| 182 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 183 | static inline bool auart_dma_enabled(struct mxs_auart_port *s) |
| 184 | { |
| 185 | return s->flags & MXS_AUART_DMA_ENABLED; |
| 186 | } |
| 187 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 188 | static void mxs_auart_stop_tx(struct uart_port *u); |
| 189 | |
| 190 | #define to_auart_port(u) container_of(u, struct mxs_auart_port, port) |
| 191 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 192 | static void mxs_auart_tx_chars(struct mxs_auart_port *s); |
| 193 | |
| 194 | static void dma_tx_callback(void *param) |
| 195 | { |
| 196 | struct mxs_auart_port *s = param; |
| 197 | struct circ_buf *xmit = &s->port.state->xmit; |
| 198 | |
| 199 | dma_unmap_sg(s->dev, &s->tx_sgl, 1, DMA_TO_DEVICE); |
| 200 | |
| 201 | /* clear the bit used to serialize the DMA tx. */ |
| 202 | clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); |
| 203 | smp_mb__after_clear_bit(); |
| 204 | |
| 205 | /* wake up the possible processes. */ |
| 206 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| 207 | uart_write_wakeup(&s->port); |
| 208 | |
| 209 | mxs_auart_tx_chars(s); |
| 210 | } |
| 211 | |
| 212 | static int mxs_auart_dma_tx(struct mxs_auart_port *s, int size) |
| 213 | { |
| 214 | struct dma_async_tx_descriptor *desc; |
| 215 | struct scatterlist *sgl = &s->tx_sgl; |
| 216 | struct dma_chan *channel = s->tx_dma_chan; |
| 217 | u32 pio; |
| 218 | |
| 219 | /* [1] : send PIO. Note, the first pio word is CTRL1. */ |
| 220 | pio = AUART_CTRL1_XFER_COUNT(size); |
| 221 | desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)&pio, |
| 222 | 1, DMA_TRANS_NONE, 0); |
| 223 | if (!desc) { |
| 224 | dev_err(s->dev, "step 1 error\n"); |
| 225 | return -EINVAL; |
| 226 | } |
| 227 | |
| 228 | /* [2] : set DMA buffer. */ |
| 229 | sg_init_one(sgl, s->tx_dma_buf, size); |
| 230 | dma_map_sg(s->dev, sgl, 1, DMA_TO_DEVICE); |
| 231 | desc = dmaengine_prep_slave_sg(channel, sgl, |
| 232 | 1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| 233 | if (!desc) { |
| 234 | dev_err(s->dev, "step 2 error\n"); |
| 235 | return -EINVAL; |
| 236 | } |
| 237 | |
| 238 | /* [3] : submit the DMA */ |
| 239 | desc->callback = dma_tx_callback; |
| 240 | desc->callback_param = s; |
| 241 | dmaengine_submit(desc); |
| 242 | dma_async_issue_pending(channel); |
| 243 | return 0; |
| 244 | } |
| 245 | |
| 246 | static void mxs_auart_tx_chars(struct mxs_auart_port *s) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 247 | { |
| 248 | struct circ_buf *xmit = &s->port.state->xmit; |
| 249 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 250 | if (auart_dma_enabled(s)) { |
fabio.estevam@freescale.com | 87b8bed | 2013-01-07 23:11:06 -0200 | [diff] [blame] | 251 | u32 i = 0; |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 252 | int size; |
| 253 | void *buffer = s->tx_dma_buf; |
| 254 | |
| 255 | if (test_and_set_bit(MXS_AUART_DMA_TX_SYNC, &s->flags)) |
| 256 | return; |
| 257 | |
| 258 | while (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { |
| 259 | size = min_t(u32, UART_XMIT_SIZE - i, |
| 260 | CIRC_CNT_TO_END(xmit->head, |
| 261 | xmit->tail, |
| 262 | UART_XMIT_SIZE)); |
| 263 | memcpy(buffer + i, xmit->buf + xmit->tail, size); |
| 264 | xmit->tail = (xmit->tail + size) & (UART_XMIT_SIZE - 1); |
| 265 | |
| 266 | i += size; |
| 267 | if (i >= UART_XMIT_SIZE) |
| 268 | break; |
| 269 | } |
| 270 | |
| 271 | if (uart_tx_stopped(&s->port)) |
| 272 | mxs_auart_stop_tx(&s->port); |
| 273 | |
| 274 | if (i) { |
| 275 | mxs_auart_dma_tx(s, i); |
| 276 | } else { |
| 277 | clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); |
| 278 | smp_mb__after_clear_bit(); |
| 279 | } |
| 280 | return; |
| 281 | } |
| 282 | |
| 283 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 284 | while (!(readl(s->port.membase + AUART_STAT) & |
| 285 | AUART_STAT_TXFF)) { |
| 286 | if (s->port.x_char) { |
| 287 | s->port.icount.tx++; |
| 288 | writel(s->port.x_char, |
| 289 | s->port.membase + AUART_DATA); |
| 290 | s->port.x_char = 0; |
| 291 | continue; |
| 292 | } |
| 293 | if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { |
| 294 | s->port.icount.tx++; |
| 295 | writel(xmit->buf[xmit->tail], |
| 296 | s->port.membase + AUART_DATA); |
| 297 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 298 | } else |
| 299 | break; |
| 300 | } |
Uwe Kleine-König | d0758a2 | 2011-11-22 14:22:56 +0100 | [diff] [blame] | 301 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| 302 | uart_write_wakeup(&s->port); |
| 303 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 304 | if (uart_circ_empty(&(s->port.state->xmit))) |
| 305 | writel(AUART_INTR_TXIEN, |
| 306 | s->port.membase + AUART_INTR_CLR); |
| 307 | else |
| 308 | writel(AUART_INTR_TXIEN, |
| 309 | s->port.membase + AUART_INTR_SET); |
| 310 | |
| 311 | if (uart_tx_stopped(&s->port)) |
| 312 | mxs_auart_stop_tx(&s->port); |
| 313 | } |
| 314 | |
| 315 | static void mxs_auart_rx_char(struct mxs_auart_port *s) |
| 316 | { |
| 317 | int flag; |
| 318 | u32 stat; |
| 319 | u8 c; |
| 320 | |
| 321 | c = readl(s->port.membase + AUART_DATA); |
| 322 | stat = readl(s->port.membase + AUART_STAT); |
| 323 | |
| 324 | flag = TTY_NORMAL; |
| 325 | s->port.icount.rx++; |
| 326 | |
| 327 | if (stat & AUART_STAT_BERR) { |
| 328 | s->port.icount.brk++; |
| 329 | if (uart_handle_break(&s->port)) |
| 330 | goto out; |
| 331 | } else if (stat & AUART_STAT_PERR) { |
| 332 | s->port.icount.parity++; |
| 333 | } else if (stat & AUART_STAT_FERR) { |
| 334 | s->port.icount.frame++; |
| 335 | } |
| 336 | |
| 337 | /* |
| 338 | * Mask off conditions which should be ingored. |
| 339 | */ |
| 340 | stat &= s->port.read_status_mask; |
| 341 | |
| 342 | if (stat & AUART_STAT_BERR) { |
| 343 | flag = TTY_BREAK; |
| 344 | } else if (stat & AUART_STAT_PERR) |
| 345 | flag = TTY_PARITY; |
| 346 | else if (stat & AUART_STAT_FERR) |
| 347 | flag = TTY_FRAME; |
| 348 | |
| 349 | if (stat & AUART_STAT_OERR) |
| 350 | s->port.icount.overrun++; |
| 351 | |
| 352 | if (uart_handle_sysrq_char(&s->port, c)) |
| 353 | goto out; |
| 354 | |
| 355 | uart_insert_char(&s->port, stat, AUART_STAT_OERR, c, flag); |
| 356 | out: |
| 357 | writel(stat, s->port.membase + AUART_STAT); |
| 358 | } |
| 359 | |
| 360 | static void mxs_auart_rx_chars(struct mxs_auart_port *s) |
| 361 | { |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 362 | u32 stat = 0; |
| 363 | |
| 364 | for (;;) { |
| 365 | stat = readl(s->port.membase + AUART_STAT); |
| 366 | if (stat & AUART_STAT_RXFE) |
| 367 | break; |
| 368 | mxs_auart_rx_char(s); |
| 369 | } |
| 370 | |
| 371 | writel(stat, s->port.membase + AUART_STAT); |
Jiri Slaby | 2e124b4 | 2013-01-03 15:53:06 +0100 | [diff] [blame] | 372 | tty_flip_buffer_push(&s->port.state->port); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 373 | } |
| 374 | |
| 375 | static int mxs_auart_request_port(struct uart_port *u) |
| 376 | { |
| 377 | return 0; |
| 378 | } |
| 379 | |
| 380 | static int mxs_auart_verify_port(struct uart_port *u, |
| 381 | struct serial_struct *ser) |
| 382 | { |
| 383 | if (u->type != PORT_UNKNOWN && u->type != PORT_IMX) |
| 384 | return -EINVAL; |
| 385 | return 0; |
| 386 | } |
| 387 | |
| 388 | static void mxs_auart_config_port(struct uart_port *u, int flags) |
| 389 | { |
| 390 | } |
| 391 | |
| 392 | static const char *mxs_auart_type(struct uart_port *u) |
| 393 | { |
| 394 | struct mxs_auart_port *s = to_auart_port(u); |
| 395 | |
| 396 | return dev_name(s->dev); |
| 397 | } |
| 398 | |
| 399 | static void mxs_auart_release_port(struct uart_port *u) |
| 400 | { |
| 401 | } |
| 402 | |
| 403 | static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl) |
| 404 | { |
| 405 | struct mxs_auart_port *s = to_auart_port(u); |
| 406 | |
| 407 | u32 ctrl = readl(u->membase + AUART_CTRL2); |
| 408 | |
Steffen Trumtrar | a683321 | 2012-12-13 14:27:43 +0100 | [diff] [blame] | 409 | ctrl &= ~(AUART_CTRL2_RTSEN | AUART_CTRL2_RTS); |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 410 | if (mctrl & TIOCM_RTS) { |
Huang Shijie | f21ec3d | 2012-08-22 22:13:36 -0400 | [diff] [blame] | 411 | if (tty_port_cts_enabled(&u->state->port)) |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 412 | ctrl |= AUART_CTRL2_RTSEN; |
Steffen Trumtrar | a683321 | 2012-12-13 14:27:43 +0100 | [diff] [blame] | 413 | else |
| 414 | ctrl |= AUART_CTRL2_RTS; |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 415 | } |
| 416 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 417 | s->ctrl = mctrl; |
| 418 | writel(ctrl, u->membase + AUART_CTRL2); |
| 419 | } |
| 420 | |
| 421 | static u32 mxs_auart_get_mctrl(struct uart_port *u) |
| 422 | { |
| 423 | struct mxs_auart_port *s = to_auart_port(u); |
| 424 | u32 stat = readl(u->membase + AUART_STAT); |
| 425 | int ctrl2 = readl(u->membase + AUART_CTRL2); |
| 426 | u32 mctrl = s->ctrl; |
| 427 | |
| 428 | mctrl &= ~TIOCM_CTS; |
| 429 | if (stat & AUART_STAT_CTS) |
| 430 | mctrl |= TIOCM_CTS; |
| 431 | |
| 432 | if (ctrl2 & AUART_CTRL2_RTS) |
| 433 | mctrl |= TIOCM_RTS; |
| 434 | |
| 435 | return mctrl; |
| 436 | } |
| 437 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 438 | static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s); |
| 439 | static void dma_rx_callback(void *arg) |
| 440 | { |
| 441 | struct mxs_auart_port *s = (struct mxs_auart_port *) arg; |
Jiri Slaby | 05c7cd3 | 2013-01-03 15:53:04 +0100 | [diff] [blame] | 442 | struct tty_port *port = &s->port.state->port; |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 443 | int count; |
| 444 | u32 stat; |
| 445 | |
Huang Shijie | d7ffb93 | 2012-11-22 15:06:30 +0800 | [diff] [blame] | 446 | dma_unmap_sg(s->dev, &s->rx_sgl, 1, DMA_FROM_DEVICE); |
| 447 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 448 | stat = readl(s->port.membase + AUART_STAT); |
| 449 | stat &= ~(AUART_STAT_OERR | AUART_STAT_BERR | |
| 450 | AUART_STAT_PERR | AUART_STAT_FERR); |
| 451 | |
| 452 | count = stat & AUART_STAT_RXCOUNT_MASK; |
Jiri Slaby | 05c7cd3 | 2013-01-03 15:53:04 +0100 | [diff] [blame] | 453 | tty_insert_flip_string(port, s->rx_dma_buf, count); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 454 | |
| 455 | writel(stat, s->port.membase + AUART_STAT); |
Jiri Slaby | 2e124b4 | 2013-01-03 15:53:06 +0100 | [diff] [blame] | 456 | tty_flip_buffer_push(port); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 457 | |
| 458 | /* start the next DMA for RX. */ |
| 459 | mxs_auart_dma_prep_rx(s); |
| 460 | } |
| 461 | |
| 462 | static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s) |
| 463 | { |
| 464 | struct dma_async_tx_descriptor *desc; |
| 465 | struct scatterlist *sgl = &s->rx_sgl; |
| 466 | struct dma_chan *channel = s->rx_dma_chan; |
| 467 | u32 pio[1]; |
| 468 | |
| 469 | /* [1] : send PIO */ |
| 470 | pio[0] = AUART_CTRL0_RXTO_ENABLE |
| 471 | | AUART_CTRL0_RXTIMEOUT(0x80) |
| 472 | | AUART_CTRL0_XFER_COUNT(UART_XMIT_SIZE); |
| 473 | desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)pio, |
| 474 | 1, DMA_TRANS_NONE, 0); |
| 475 | if (!desc) { |
| 476 | dev_err(s->dev, "step 1 error\n"); |
| 477 | return -EINVAL; |
| 478 | } |
| 479 | |
| 480 | /* [2] : send DMA request */ |
| 481 | sg_init_one(sgl, s->rx_dma_buf, UART_XMIT_SIZE); |
| 482 | dma_map_sg(s->dev, sgl, 1, DMA_FROM_DEVICE); |
| 483 | desc = dmaengine_prep_slave_sg(channel, sgl, 1, DMA_DEV_TO_MEM, |
| 484 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| 485 | if (!desc) { |
| 486 | dev_err(s->dev, "step 2 error\n"); |
| 487 | return -1; |
| 488 | } |
| 489 | |
| 490 | /* [3] : submit the DMA, but do not issue it. */ |
| 491 | desc->callback = dma_rx_callback; |
| 492 | desc->callback_param = s; |
| 493 | dmaengine_submit(desc); |
| 494 | dma_async_issue_pending(channel); |
| 495 | return 0; |
| 496 | } |
| 497 | |
| 498 | static void mxs_auart_dma_exit_channel(struct mxs_auart_port *s) |
| 499 | { |
| 500 | if (s->tx_dma_chan) { |
| 501 | dma_release_channel(s->tx_dma_chan); |
| 502 | s->tx_dma_chan = NULL; |
| 503 | } |
| 504 | if (s->rx_dma_chan) { |
| 505 | dma_release_channel(s->rx_dma_chan); |
| 506 | s->rx_dma_chan = NULL; |
| 507 | } |
| 508 | |
| 509 | kfree(s->tx_dma_buf); |
| 510 | kfree(s->rx_dma_buf); |
| 511 | s->tx_dma_buf = NULL; |
| 512 | s->rx_dma_buf = NULL; |
| 513 | } |
| 514 | |
| 515 | static void mxs_auart_dma_exit(struct mxs_auart_port *s) |
| 516 | { |
| 517 | |
| 518 | writel(AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE | AUART_CTRL2_DMAONERR, |
| 519 | s->port.membase + AUART_CTRL2_CLR); |
| 520 | |
| 521 | mxs_auart_dma_exit_channel(s); |
| 522 | s->flags &= ~MXS_AUART_DMA_ENABLED; |
| 523 | clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); |
| 524 | clear_bit(MXS_AUART_DMA_RX_READY, &s->flags); |
| 525 | } |
| 526 | |
| 527 | static int mxs_auart_dma_init(struct mxs_auart_port *s) |
| 528 | { |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 529 | if (auart_dma_enabled(s)) |
| 530 | return 0; |
| 531 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 532 | /* init for RX */ |
Shawn Guo | bcc20f9 | 2013-02-26 13:47:41 +0800 | [diff] [blame] | 533 | s->rx_dma_chan = dma_request_slave_channel(s->dev, "rx"); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 534 | if (!s->rx_dma_chan) |
| 535 | goto err_out; |
| 536 | s->rx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); |
| 537 | if (!s->rx_dma_buf) |
| 538 | goto err_out; |
| 539 | |
| 540 | /* init for TX */ |
Shawn Guo | bcc20f9 | 2013-02-26 13:47:41 +0800 | [diff] [blame] | 541 | s->tx_dma_chan = dma_request_slave_channel(s->dev, "tx"); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 542 | if (!s->tx_dma_chan) |
| 543 | goto err_out; |
| 544 | s->tx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); |
| 545 | if (!s->tx_dma_buf) |
| 546 | goto err_out; |
| 547 | |
| 548 | /* set the flags */ |
| 549 | s->flags |= MXS_AUART_DMA_ENABLED; |
| 550 | dev_dbg(s->dev, "enabled the DMA support."); |
| 551 | |
Hector Palacios | 9987f76 | 2013-10-03 09:32:03 +0200 | [diff] [blame] | 552 | /* The DMA buffer is now the FIFO the TTY subsystem can use */ |
| 553 | s->port.fifosize = UART_XMIT_SIZE; |
| 554 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 555 | return 0; |
| 556 | |
| 557 | err_out: |
| 558 | mxs_auart_dma_exit_channel(s); |
| 559 | return -EINVAL; |
| 560 | |
| 561 | } |
| 562 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 563 | static void mxs_auart_settermios(struct uart_port *u, |
| 564 | struct ktermios *termios, |
| 565 | struct ktermios *old) |
| 566 | { |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 567 | struct mxs_auart_port *s = to_auart_port(u); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 568 | u32 bm, ctrl, ctrl2, div; |
| 569 | unsigned int cflag, baud; |
| 570 | |
| 571 | cflag = termios->c_cflag; |
| 572 | |
| 573 | ctrl = AUART_LINECTRL_FEN; |
| 574 | ctrl2 = readl(u->membase + AUART_CTRL2); |
| 575 | |
| 576 | /* byte size */ |
| 577 | switch (cflag & CSIZE) { |
| 578 | case CS5: |
| 579 | bm = 0; |
| 580 | break; |
| 581 | case CS6: |
| 582 | bm = 1; |
| 583 | break; |
| 584 | case CS7: |
| 585 | bm = 2; |
| 586 | break; |
| 587 | case CS8: |
| 588 | bm = 3; |
| 589 | break; |
| 590 | default: |
| 591 | return; |
| 592 | } |
| 593 | |
| 594 | ctrl |= AUART_LINECTRL_WLEN(bm); |
| 595 | |
| 596 | /* parity */ |
| 597 | if (cflag & PARENB) { |
| 598 | ctrl |= AUART_LINECTRL_PEN; |
| 599 | if ((cflag & PARODD) == 0) |
| 600 | ctrl |= AUART_LINECTRL_EPS; |
| 601 | } |
| 602 | |
| 603 | u->read_status_mask = 0; |
| 604 | |
| 605 | if (termios->c_iflag & INPCK) |
| 606 | u->read_status_mask |= AUART_STAT_PERR; |
| 607 | if (termios->c_iflag & (BRKINT | PARMRK)) |
| 608 | u->read_status_mask |= AUART_STAT_BERR; |
| 609 | |
| 610 | /* |
| 611 | * Characters to ignore |
| 612 | */ |
| 613 | u->ignore_status_mask = 0; |
| 614 | if (termios->c_iflag & IGNPAR) |
| 615 | u->ignore_status_mask |= AUART_STAT_PERR; |
| 616 | if (termios->c_iflag & IGNBRK) { |
| 617 | u->ignore_status_mask |= AUART_STAT_BERR; |
| 618 | /* |
| 619 | * If we're ignoring parity and break indicators, |
| 620 | * ignore overruns too (for real raw support). |
| 621 | */ |
| 622 | if (termios->c_iflag & IGNPAR) |
| 623 | u->ignore_status_mask |= AUART_STAT_OERR; |
| 624 | } |
| 625 | |
| 626 | /* |
| 627 | * ignore all characters if CREAD is not set |
| 628 | */ |
| 629 | if (cflag & CREAD) |
| 630 | ctrl2 |= AUART_CTRL2_RXE; |
| 631 | else |
| 632 | ctrl2 &= ~AUART_CTRL2_RXE; |
| 633 | |
| 634 | /* figure out the stop bits requested */ |
| 635 | if (cflag & CSTOPB) |
| 636 | ctrl |= AUART_LINECTRL_STP2; |
| 637 | |
| 638 | /* figure out the hardware flow control settings */ |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 639 | if (cflag & CRTSCTS) { |
| 640 | /* |
| 641 | * The DMA has a bug(see errata:2836) in mx23. |
| 642 | * So we can not implement the DMA for auart in mx23, |
| 643 | * we can only implement the DMA support for auart |
| 644 | * in mx28. |
| 645 | */ |
Huang Shijie | afab220 | 2013-08-03 10:09:15 -0400 | [diff] [blame] | 646 | if (is_imx28_auart(s) |
Huang Shijie | 8418e67 | 2013-08-03 10:09:14 -0400 | [diff] [blame] | 647 | && test_bit(MXS_AUART_RTSCTS, &s->flags)) { |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 648 | if (!mxs_auart_dma_init(s)) |
| 649 | /* enable DMA tranfer */ |
| 650 | ctrl2 |= AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE |
| 651 | | AUART_CTRL2_DMAONERR; |
| 652 | } |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 653 | ctrl2 |= AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN; |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 654 | } else { |
Huang Shijie | 0059202 | 2012-08-08 10:37:59 +0800 | [diff] [blame] | 655 | ctrl2 &= ~(AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 656 | } |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 657 | |
| 658 | /* set baud rate */ |
| 659 | baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk); |
| 660 | div = u->uartclk * 32 / baud; |
| 661 | ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); |
| 662 | ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6); |
| 663 | |
| 664 | writel(ctrl, u->membase + AUART_LINECTRL); |
| 665 | writel(ctrl2, u->membase + AUART_CTRL2); |
Lothar Waßmann | 8b979f7 | 2012-05-03 11:37:12 +0200 | [diff] [blame] | 666 | |
| 667 | uart_update_timeout(u, termios->c_cflag, baud); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 668 | |
| 669 | /* prepare for the DMA RX. */ |
| 670 | if (auart_dma_enabled(s) && |
| 671 | !test_and_set_bit(MXS_AUART_DMA_RX_READY, &s->flags)) { |
| 672 | if (!mxs_auart_dma_prep_rx(s)) { |
| 673 | /* Disable the normal RX interrupt. */ |
Huang Shijie | a591944 | 2012-11-22 15:06:29 +0800 | [diff] [blame] | 674 | writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN, |
| 675 | u->membase + AUART_INTR_CLR); |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 676 | } else { |
| 677 | mxs_auart_dma_exit(s); |
| 678 | dev_err(s->dev, "We can not start up the DMA.\n"); |
| 679 | } |
| 680 | } |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 681 | } |
| 682 | |
| 683 | static irqreturn_t mxs_auart_irq_handle(int irq, void *context) |
| 684 | { |
Uwe Kleine-König | d970d7f | 2013-07-04 11:28:51 +0200 | [diff] [blame] | 685 | u32 istat; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 686 | struct mxs_auart_port *s = context; |
| 687 | u32 stat = readl(s->port.membase + AUART_STAT); |
| 688 | |
Uwe Kleine-König | d970d7f | 2013-07-04 11:28:51 +0200 | [diff] [blame] | 689 | istat = readl(s->port.membase + AUART_INTR); |
| 690 | |
| 691 | /* ack irq */ |
| 692 | writel(istat & (AUART_INTR_RTIS |
| 693 | | AUART_INTR_TXIS |
| 694 | | AUART_INTR_RXIS |
| 695 | | AUART_INTR_CTSMIS), |
| 696 | s->port.membase + AUART_INTR_CLR); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 697 | |
| 698 | if (istat & AUART_INTR_CTSMIS) { |
| 699 | uart_handle_cts_change(&s->port, stat & AUART_STAT_CTS); |
| 700 | writel(AUART_INTR_CTSMIS, |
| 701 | s->port.membase + AUART_INTR_CLR); |
| 702 | istat &= ~AUART_INTR_CTSMIS; |
| 703 | } |
| 704 | |
| 705 | if (istat & (AUART_INTR_RTIS | AUART_INTR_RXIS)) { |
Huang Shijie | a591944 | 2012-11-22 15:06:29 +0800 | [diff] [blame] | 706 | if (!auart_dma_enabled(s)) |
| 707 | mxs_auart_rx_chars(s); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 708 | istat &= ~(AUART_INTR_RTIS | AUART_INTR_RXIS); |
| 709 | } |
| 710 | |
| 711 | if (istat & AUART_INTR_TXIS) { |
| 712 | mxs_auart_tx_chars(s); |
| 713 | istat &= ~AUART_INTR_TXIS; |
| 714 | } |
| 715 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 716 | return IRQ_HANDLED; |
| 717 | } |
| 718 | |
| 719 | static void mxs_auart_reset(struct uart_port *u) |
| 720 | { |
| 721 | int i; |
| 722 | unsigned int reg; |
| 723 | |
| 724 | writel(AUART_CTRL0_SFTRST, u->membase + AUART_CTRL0_CLR); |
| 725 | |
| 726 | for (i = 0; i < 10000; i++) { |
| 727 | reg = readl(u->membase + AUART_CTRL0); |
| 728 | if (!(reg & AUART_CTRL0_SFTRST)) |
| 729 | break; |
| 730 | udelay(3); |
| 731 | } |
| 732 | writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR); |
| 733 | } |
| 734 | |
| 735 | static int mxs_auart_startup(struct uart_port *u) |
| 736 | { |
Fabio Estevam | 9bbc3dc | 2013-12-02 01:17:58 -0200 | [diff] [blame^] | 737 | int ret; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 738 | struct mxs_auart_port *s = to_auart_port(u); |
| 739 | |
Fabio Estevam | 9bbc3dc | 2013-12-02 01:17:58 -0200 | [diff] [blame^] | 740 | ret = clk_prepare_enable(s->clk); |
| 741 | if (ret) |
| 742 | return ret; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 743 | |
| 744 | writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR); |
| 745 | |
| 746 | writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_SET); |
| 747 | |
| 748 | writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, |
| 749 | u->membase + AUART_INTR); |
| 750 | |
Hector Palacios | 9987f76 | 2013-10-03 09:32:03 +0200 | [diff] [blame] | 751 | /* Reset FIFO size (it could have changed if DMA was enabled) */ |
| 752 | u->fifosize = MXS_AUART_FIFO_SIZE; |
| 753 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 754 | /* |
| 755 | * Enable fifo so all four bytes of a DMA word are written to |
| 756 | * output (otherwise, only the LSB is written, ie. 1 in 4 bytes) |
| 757 | */ |
| 758 | writel(AUART_LINECTRL_FEN, u->membase + AUART_LINECTRL_SET); |
| 759 | |
| 760 | return 0; |
| 761 | } |
| 762 | |
| 763 | static void mxs_auart_shutdown(struct uart_port *u) |
| 764 | { |
| 765 | struct mxs_auart_port *s = to_auart_port(u); |
| 766 | |
Huang Shijie | e800163 | 2012-11-16 16:03:53 +0800 | [diff] [blame] | 767 | if (auart_dma_enabled(s)) |
| 768 | mxs_auart_dma_exit(s); |
| 769 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 770 | writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR); |
| 771 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 772 | writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, |
| 773 | u->membase + AUART_INTR_CLR); |
| 774 | |
Huang Shijie | 851b714 | 2012-09-06 22:38:40 -0400 | [diff] [blame] | 775 | writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET); |
| 776 | |
Shawn Guo | a481377 | 2011-12-20 14:10:29 +0800 | [diff] [blame] | 777 | clk_disable_unprepare(s->clk); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 778 | } |
| 779 | |
| 780 | static unsigned int mxs_auart_tx_empty(struct uart_port *u) |
| 781 | { |
| 782 | if (readl(u->membase + AUART_STAT) & AUART_STAT_TXFE) |
| 783 | return TIOCSER_TEMT; |
| 784 | else |
| 785 | return 0; |
| 786 | } |
| 787 | |
| 788 | static void mxs_auart_start_tx(struct uart_port *u) |
| 789 | { |
| 790 | struct mxs_auart_port *s = to_auart_port(u); |
| 791 | |
| 792 | /* enable transmitter */ |
| 793 | writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_SET); |
| 794 | |
| 795 | mxs_auart_tx_chars(s); |
| 796 | } |
| 797 | |
| 798 | static void mxs_auart_stop_tx(struct uart_port *u) |
| 799 | { |
| 800 | writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_CLR); |
| 801 | } |
| 802 | |
| 803 | static void mxs_auart_stop_rx(struct uart_port *u) |
| 804 | { |
| 805 | writel(AUART_CTRL2_RXE, u->membase + AUART_CTRL2_CLR); |
| 806 | } |
| 807 | |
| 808 | static void mxs_auart_break_ctl(struct uart_port *u, int ctl) |
| 809 | { |
| 810 | if (ctl) |
| 811 | writel(AUART_LINECTRL_BRK, |
| 812 | u->membase + AUART_LINECTRL_SET); |
| 813 | else |
| 814 | writel(AUART_LINECTRL_BRK, |
| 815 | u->membase + AUART_LINECTRL_CLR); |
| 816 | } |
| 817 | |
| 818 | static void mxs_auart_enable_ms(struct uart_port *port) |
| 819 | { |
| 820 | /* just empty */ |
| 821 | } |
| 822 | |
| 823 | static struct uart_ops mxs_auart_ops = { |
| 824 | .tx_empty = mxs_auart_tx_empty, |
| 825 | .start_tx = mxs_auart_start_tx, |
| 826 | .stop_tx = mxs_auart_stop_tx, |
| 827 | .stop_rx = mxs_auart_stop_rx, |
| 828 | .enable_ms = mxs_auart_enable_ms, |
| 829 | .break_ctl = mxs_auart_break_ctl, |
| 830 | .set_mctrl = mxs_auart_set_mctrl, |
| 831 | .get_mctrl = mxs_auart_get_mctrl, |
| 832 | .startup = mxs_auart_startup, |
| 833 | .shutdown = mxs_auart_shutdown, |
| 834 | .set_termios = mxs_auart_settermios, |
| 835 | .type = mxs_auart_type, |
| 836 | .release_port = mxs_auart_release_port, |
| 837 | .request_port = mxs_auart_request_port, |
| 838 | .config_port = mxs_auart_config_port, |
| 839 | .verify_port = mxs_auart_verify_port, |
| 840 | }; |
| 841 | |
| 842 | static struct mxs_auart_port *auart_port[MXS_AUART_PORTS]; |
| 843 | |
| 844 | #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE |
| 845 | static void mxs_auart_console_putchar(struct uart_port *port, int ch) |
| 846 | { |
| 847 | unsigned int to = 1000; |
| 848 | |
| 849 | while (readl(port->membase + AUART_STAT) & AUART_STAT_TXFF) { |
| 850 | if (!to--) |
| 851 | break; |
| 852 | udelay(1); |
| 853 | } |
| 854 | |
| 855 | writel(ch, port->membase + AUART_DATA); |
| 856 | } |
| 857 | |
| 858 | static void |
| 859 | auart_console_write(struct console *co, const char *str, unsigned int count) |
| 860 | { |
| 861 | struct mxs_auart_port *s; |
| 862 | struct uart_port *port; |
| 863 | unsigned int old_ctrl0, old_ctrl2; |
Uwe Kleine-König | 079a036 | 2013-06-28 11:49:41 +0200 | [diff] [blame] | 864 | unsigned int to = 20000; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 865 | |
Wolfram Sang | 4829e76 | 2013-04-19 21:12:17 +0200 | [diff] [blame] | 866 | if (co->index >= MXS_AUART_PORTS || co->index < 0) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 867 | return; |
| 868 | |
| 869 | s = auart_port[co->index]; |
| 870 | port = &s->port; |
| 871 | |
| 872 | clk_enable(s->clk); |
| 873 | |
| 874 | /* First save the CR then disable the interrupts */ |
| 875 | old_ctrl2 = readl(port->membase + AUART_CTRL2); |
| 876 | old_ctrl0 = readl(port->membase + AUART_CTRL0); |
| 877 | |
| 878 | writel(AUART_CTRL0_CLKGATE, |
| 879 | port->membase + AUART_CTRL0_CLR); |
| 880 | writel(AUART_CTRL2_UARTEN | AUART_CTRL2_TXE, |
| 881 | port->membase + AUART_CTRL2_SET); |
| 882 | |
| 883 | uart_console_write(port, str, count, mxs_auart_console_putchar); |
| 884 | |
Uwe Kleine-König | 079a036 | 2013-06-28 11:49:41 +0200 | [diff] [blame] | 885 | /* Finally, wait for transmitter to become empty ... */ |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 886 | while (readl(port->membase + AUART_STAT) & AUART_STAT_BUSY) { |
Uwe Kleine-König | 079a036 | 2013-06-28 11:49:41 +0200 | [diff] [blame] | 887 | udelay(1); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 888 | if (!to--) |
| 889 | break; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 890 | } |
| 891 | |
Uwe Kleine-König | 079a036 | 2013-06-28 11:49:41 +0200 | [diff] [blame] | 892 | /* |
| 893 | * ... and restore the TCR if we waited long enough for the transmitter |
| 894 | * to be idle. This might keep the transmitter enabled although it is |
| 895 | * unused, but that is better than to disable it while it is still |
| 896 | * transmitting. |
| 897 | */ |
| 898 | if (!(readl(port->membase + AUART_STAT) & AUART_STAT_BUSY)) { |
| 899 | writel(old_ctrl0, port->membase + AUART_CTRL0); |
| 900 | writel(old_ctrl2, port->membase + AUART_CTRL2); |
| 901 | } |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 902 | |
| 903 | clk_disable(s->clk); |
| 904 | } |
| 905 | |
| 906 | static void __init |
| 907 | auart_console_get_options(struct uart_port *port, int *baud, |
| 908 | int *parity, int *bits) |
| 909 | { |
| 910 | unsigned int lcr_h, quot; |
| 911 | |
| 912 | if (!(readl(port->membase + AUART_CTRL2) & AUART_CTRL2_UARTEN)) |
| 913 | return; |
| 914 | |
| 915 | lcr_h = readl(port->membase + AUART_LINECTRL); |
| 916 | |
| 917 | *parity = 'n'; |
| 918 | if (lcr_h & AUART_LINECTRL_PEN) { |
| 919 | if (lcr_h & AUART_LINECTRL_EPS) |
| 920 | *parity = 'e'; |
| 921 | else |
| 922 | *parity = 'o'; |
| 923 | } |
| 924 | |
| 925 | if ((lcr_h & AUART_LINECTRL_WLEN_MASK) == AUART_LINECTRL_WLEN(2)) |
| 926 | *bits = 7; |
| 927 | else |
| 928 | *bits = 8; |
| 929 | |
| 930 | quot = ((readl(port->membase + AUART_LINECTRL) |
| 931 | & AUART_LINECTRL_BAUD_DIVINT_MASK)) |
| 932 | >> (AUART_LINECTRL_BAUD_DIVINT_SHIFT - 6); |
| 933 | quot |= ((readl(port->membase + AUART_LINECTRL) |
| 934 | & AUART_LINECTRL_BAUD_DIVFRAC_MASK)) |
| 935 | >> AUART_LINECTRL_BAUD_DIVFRAC_SHIFT; |
| 936 | if (quot == 0) |
| 937 | quot = 1; |
| 938 | |
| 939 | *baud = (port->uartclk << 2) / quot; |
| 940 | } |
| 941 | |
| 942 | static int __init |
| 943 | auart_console_setup(struct console *co, char *options) |
| 944 | { |
| 945 | struct mxs_auart_port *s; |
| 946 | int baud = 9600; |
| 947 | int bits = 8; |
| 948 | int parity = 'n'; |
| 949 | int flow = 'n'; |
| 950 | int ret; |
| 951 | |
| 952 | /* |
| 953 | * Check whether an invalid uart number has been specified, and |
| 954 | * if so, search for the first available port that does have |
| 955 | * console support. |
| 956 | */ |
| 957 | if (co->index == -1 || co->index >= ARRAY_SIZE(auart_port)) |
| 958 | co->index = 0; |
| 959 | s = auart_port[co->index]; |
| 960 | if (!s) |
| 961 | return -ENODEV; |
| 962 | |
Fabio Estevam | 9bbc3dc | 2013-12-02 01:17:58 -0200 | [diff] [blame^] | 963 | ret = clk_prepare_enable(s->clk); |
| 964 | if (ret) |
| 965 | return ret; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 966 | |
| 967 | if (options) |
| 968 | uart_parse_options(options, &baud, &parity, &bits, &flow); |
| 969 | else |
| 970 | auart_console_get_options(&s->port, &baud, &parity, &bits); |
| 971 | |
| 972 | ret = uart_set_options(&s->port, co, baud, parity, bits, flow); |
| 973 | |
Shawn Guo | a481377 | 2011-12-20 14:10:29 +0800 | [diff] [blame] | 974 | clk_disable_unprepare(s->clk); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 975 | |
| 976 | return ret; |
| 977 | } |
| 978 | |
| 979 | static struct console auart_console = { |
| 980 | .name = "ttyAPP", |
| 981 | .write = auart_console_write, |
| 982 | .device = uart_console_device, |
| 983 | .setup = auart_console_setup, |
| 984 | .flags = CON_PRINTBUFFER, |
| 985 | .index = -1, |
| 986 | .data = &auart_driver, |
| 987 | }; |
| 988 | #endif |
| 989 | |
| 990 | static struct uart_driver auart_driver = { |
| 991 | .owner = THIS_MODULE, |
| 992 | .driver_name = "ttyAPP", |
| 993 | .dev_name = "ttyAPP", |
| 994 | .major = 0, |
| 995 | .minor = 0, |
| 996 | .nr = MXS_AUART_PORTS, |
| 997 | #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE |
| 998 | .cons = &auart_console, |
| 999 | #endif |
| 1000 | }; |
| 1001 | |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1002 | /* |
| 1003 | * This function returns 1 if pdev isn't a device instatiated by dt, 0 if it |
| 1004 | * could successfully get all information from dt or a negative errno. |
| 1005 | */ |
| 1006 | static int serial_mxs_probe_dt(struct mxs_auart_port *s, |
| 1007 | struct platform_device *pdev) |
| 1008 | { |
| 1009 | struct device_node *np = pdev->dev.of_node; |
| 1010 | int ret; |
| 1011 | |
| 1012 | if (!np) |
| 1013 | /* no device tree device */ |
| 1014 | return 1; |
| 1015 | |
| 1016 | ret = of_alias_get_id(np, "serial"); |
| 1017 | if (ret < 0) { |
| 1018 | dev_err(&pdev->dev, "failed to get alias id: %d\n", ret); |
| 1019 | return ret; |
| 1020 | } |
| 1021 | s->port.line = ret; |
| 1022 | |
Huang Shijie | 8418e67 | 2013-08-03 10:09:14 -0400 | [diff] [blame] | 1023 | if (of_get_property(np, "fsl,uart-has-rtscts", NULL)) |
| 1024 | set_bit(MXS_AUART_RTSCTS, &s->flags); |
| 1025 | |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1026 | return 0; |
| 1027 | } |
| 1028 | |
Bill Pemberton | 9671f09 | 2012-11-19 13:21:50 -0500 | [diff] [blame] | 1029 | static int mxs_auart_probe(struct platform_device *pdev) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1030 | { |
Huang Shijie | f4b1f03b | 2012-11-16 16:03:52 +0800 | [diff] [blame] | 1031 | const struct of_device_id *of_id = |
| 1032 | of_match_device(mxs_auart_dt_ids, &pdev->dev); |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1033 | struct mxs_auart_port *s; |
| 1034 | u32 version; |
| 1035 | int ret = 0; |
| 1036 | struct resource *r; |
| 1037 | |
| 1038 | s = kzalloc(sizeof(struct mxs_auart_port), GFP_KERNEL); |
| 1039 | if (!s) { |
| 1040 | ret = -ENOMEM; |
| 1041 | goto out; |
| 1042 | } |
| 1043 | |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1044 | ret = serial_mxs_probe_dt(s, pdev); |
| 1045 | if (ret > 0) |
| 1046 | s->port.line = pdev->id < 0 ? 0 : pdev->id; |
| 1047 | else if (ret < 0) |
| 1048 | goto out_free; |
| 1049 | |
Huang Shijie | f4b1f03b | 2012-11-16 16:03:52 +0800 | [diff] [blame] | 1050 | if (of_id) { |
| 1051 | pdev->id_entry = of_id->data; |
| 1052 | s->devtype = pdev->id_entry->driver_data; |
| 1053 | } |
| 1054 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1055 | s->clk = clk_get(&pdev->dev, NULL); |
| 1056 | if (IS_ERR(s->clk)) { |
| 1057 | ret = PTR_ERR(s->clk); |
| 1058 | goto out_free; |
| 1059 | } |
| 1060 | |
| 1061 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 1062 | if (!r) { |
| 1063 | ret = -ENXIO; |
| 1064 | goto out_free_clk; |
| 1065 | } |
| 1066 | |
| 1067 | s->port.mapbase = r->start; |
| 1068 | s->port.membase = ioremap(r->start, resource_size(r)); |
| 1069 | s->port.ops = &mxs_auart_ops; |
| 1070 | s->port.iotype = UPIO_MEM; |
Hector Palacios | 9987f76 | 2013-10-03 09:32:03 +0200 | [diff] [blame] | 1071 | s->port.fifosize = MXS_AUART_FIFO_SIZE; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1072 | s->port.uartclk = clk_get_rate(s->clk); |
| 1073 | s->port.type = PORT_IMX; |
Wolfram Sang | 4c24f2c | 2013-04-19 21:06:20 +0200 | [diff] [blame] | 1074 | s->port.dev = s->dev = &pdev->dev; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1075 | |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1076 | s->ctrl = 0; |
| 1077 | |
| 1078 | s->irq = platform_get_irq(pdev, 0); |
| 1079 | s->port.irq = s->irq; |
| 1080 | ret = request_irq(s->irq, mxs_auart_irq_handle, 0, dev_name(&pdev->dev), s); |
| 1081 | if (ret) |
| 1082 | goto out_free_clk; |
| 1083 | |
| 1084 | platform_set_drvdata(pdev, s); |
| 1085 | |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1086 | auart_port[s->port.line] = s; |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1087 | |
| 1088 | mxs_auart_reset(&s->port); |
| 1089 | |
| 1090 | ret = uart_add_one_port(&auart_driver, &s->port); |
| 1091 | if (ret) |
| 1092 | goto out_free_irq; |
| 1093 | |
| 1094 | version = readl(s->port.membase + AUART_VERSION); |
| 1095 | dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n", |
| 1096 | (version >> 24) & 0xff, |
| 1097 | (version >> 16) & 0xff, version & 0xffff); |
| 1098 | |
| 1099 | return 0; |
| 1100 | |
| 1101 | out_free_irq: |
| 1102 | auart_port[pdev->id] = NULL; |
| 1103 | free_irq(s->irq, s); |
| 1104 | out_free_clk: |
| 1105 | clk_put(s->clk); |
| 1106 | out_free: |
| 1107 | kfree(s); |
| 1108 | out: |
| 1109 | return ret; |
| 1110 | } |
| 1111 | |
Bill Pemberton | ae8d8a1 | 2012-11-19 13:26:18 -0500 | [diff] [blame] | 1112 | static int mxs_auart_remove(struct platform_device *pdev) |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1113 | { |
| 1114 | struct mxs_auart_port *s = platform_get_drvdata(pdev); |
| 1115 | |
| 1116 | uart_remove_one_port(&auart_driver, &s->port); |
| 1117 | |
| 1118 | auart_port[pdev->id] = NULL; |
| 1119 | |
| 1120 | clk_put(s->clk); |
| 1121 | free_irq(s->irq, s); |
| 1122 | kfree(s); |
| 1123 | |
| 1124 | return 0; |
| 1125 | } |
| 1126 | |
| 1127 | static struct platform_driver mxs_auart_driver = { |
| 1128 | .probe = mxs_auart_probe, |
Bill Pemberton | 2d47b71 | 2012-11-19 13:21:34 -0500 | [diff] [blame] | 1129 | .remove = mxs_auart_remove, |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1130 | .driver = { |
| 1131 | .name = "mxs-auart", |
| 1132 | .owner = THIS_MODULE, |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1133 | .of_match_table = mxs_auart_dt_ids, |
Sascha Hauer | 47d37d6 | 2011-01-11 15:54:54 +0100 | [diff] [blame] | 1134 | }, |
| 1135 | }; |
| 1136 | |
| 1137 | static int __init mxs_auart_init(void) |
| 1138 | { |
| 1139 | int r; |
| 1140 | |
| 1141 | r = uart_register_driver(&auart_driver); |
| 1142 | if (r) |
| 1143 | goto out; |
| 1144 | |
| 1145 | r = platform_driver_register(&mxs_auart_driver); |
| 1146 | if (r) |
| 1147 | goto out_err; |
| 1148 | |
| 1149 | return 0; |
| 1150 | out_err: |
| 1151 | uart_unregister_driver(&auart_driver); |
| 1152 | out: |
| 1153 | return r; |
| 1154 | } |
| 1155 | |
| 1156 | static void __exit mxs_auart_exit(void) |
| 1157 | { |
| 1158 | platform_driver_unregister(&mxs_auart_driver); |
| 1159 | uart_unregister_driver(&auart_driver); |
| 1160 | } |
| 1161 | |
| 1162 | module_init(mxs_auart_init); |
| 1163 | module_exit(mxs_auart_exit); |
| 1164 | MODULE_LICENSE("GPL"); |
| 1165 | MODULE_DESCRIPTION("Freescale MXS application uart driver"); |
Fabio Estevam | 1ea6607 | 2012-06-18 10:06:09 -0300 | [diff] [blame] | 1166 | MODULE_ALIAS("platform:mxs-auart"); |