Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 - 2014 Allwinner Tech |
| 3 | * Pan Nan <pannan@allwinnertech.com> |
| 4 | * |
| 5 | * Copyright (C) 2014 Maxime Ripard |
| 6 | * Maxime Ripard <maxime.ripard@free-electrons.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License as |
| 10 | * published by the Free Software Foundation; either version 2 of |
| 11 | * the License, or (at your option) any later version. |
| 12 | */ |
| 13 | |
| 14 | #include <linux/clk.h> |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/device.h> |
| 17 | #include <linux/interrupt.h> |
| 18 | #include <linux/io.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/platform_device.h> |
| 21 | #include <linux/pm_runtime.h> |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 22 | |
| 23 | #include <linux/spi/spi.h> |
| 24 | |
| 25 | #define SUN4I_FIFO_DEPTH 64 |
| 26 | |
| 27 | #define SUN4I_RXDATA_REG 0x00 |
| 28 | |
| 29 | #define SUN4I_TXDATA_REG 0x04 |
| 30 | |
| 31 | #define SUN4I_CTL_REG 0x08 |
| 32 | #define SUN4I_CTL_ENABLE BIT(0) |
| 33 | #define SUN4I_CTL_MASTER BIT(1) |
| 34 | #define SUN4I_CTL_CPHA BIT(2) |
| 35 | #define SUN4I_CTL_CPOL BIT(3) |
| 36 | #define SUN4I_CTL_CS_ACTIVE_LOW BIT(4) |
| 37 | #define SUN4I_CTL_LMTF BIT(6) |
| 38 | #define SUN4I_CTL_TF_RST BIT(8) |
| 39 | #define SUN4I_CTL_RF_RST BIT(9) |
| 40 | #define SUN4I_CTL_XCH BIT(10) |
| 41 | #define SUN4I_CTL_CS_MASK 0x3000 |
| 42 | #define SUN4I_CTL_CS(cs) (((cs) << 12) & SUN4I_CTL_CS_MASK) |
| 43 | #define SUN4I_CTL_DHB BIT(15) |
| 44 | #define SUN4I_CTL_CS_MANUAL BIT(16) |
| 45 | #define SUN4I_CTL_CS_LEVEL BIT(17) |
| 46 | #define SUN4I_CTL_TP BIT(18) |
| 47 | |
| 48 | #define SUN4I_INT_CTL_REG 0x0c |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 49 | #define SUN4I_INT_CTL_RF_F34 BIT(4) |
| 50 | #define SUN4I_INT_CTL_TF_E34 BIT(12) |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 51 | #define SUN4I_INT_CTL_TC BIT(16) |
| 52 | |
| 53 | #define SUN4I_INT_STA_REG 0x10 |
| 54 | |
| 55 | #define SUN4I_DMA_CTL_REG 0x14 |
| 56 | |
| 57 | #define SUN4I_WAIT_REG 0x18 |
| 58 | |
| 59 | #define SUN4I_CLK_CTL_REG 0x1c |
| 60 | #define SUN4I_CLK_CTL_CDR2_MASK 0xff |
| 61 | #define SUN4I_CLK_CTL_CDR2(div) ((div) & SUN4I_CLK_CTL_CDR2_MASK) |
| 62 | #define SUN4I_CLK_CTL_CDR1_MASK 0xf |
| 63 | #define SUN4I_CLK_CTL_CDR1(div) (((div) & SUN4I_CLK_CTL_CDR1_MASK) << 8) |
| 64 | #define SUN4I_CLK_CTL_DRS BIT(12) |
| 65 | |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 66 | #define SUN4I_MAX_XFER_SIZE 0xffffff |
| 67 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 68 | #define SUN4I_BURST_CNT_REG 0x20 |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 69 | #define SUN4I_BURST_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE) |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 70 | |
| 71 | #define SUN4I_XMIT_CNT_REG 0x24 |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 72 | #define SUN4I_XMIT_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE) |
| 73 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 74 | |
| 75 | #define SUN4I_FIFO_STA_REG 0x28 |
| 76 | #define SUN4I_FIFO_STA_RF_CNT_MASK 0x7f |
| 77 | #define SUN4I_FIFO_STA_RF_CNT_BITS 0 |
| 78 | #define SUN4I_FIFO_STA_TF_CNT_MASK 0x7f |
| 79 | #define SUN4I_FIFO_STA_TF_CNT_BITS 16 |
| 80 | |
| 81 | struct sun4i_spi { |
| 82 | struct spi_master *master; |
| 83 | void __iomem *base_addr; |
| 84 | struct clk *hclk; |
| 85 | struct clk *mclk; |
| 86 | |
| 87 | struct completion done; |
| 88 | |
| 89 | const u8 *tx_buf; |
| 90 | u8 *rx_buf; |
| 91 | int len; |
| 92 | }; |
| 93 | |
| 94 | static inline u32 sun4i_spi_read(struct sun4i_spi *sspi, u32 reg) |
| 95 | { |
| 96 | return readl(sspi->base_addr + reg); |
| 97 | } |
| 98 | |
| 99 | static inline void sun4i_spi_write(struct sun4i_spi *sspi, u32 reg, u32 value) |
| 100 | { |
| 101 | writel(value, sspi->base_addr + reg); |
| 102 | } |
| 103 | |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 104 | static inline u32 sun4i_spi_get_tx_fifo_count(struct sun4i_spi *sspi) |
| 105 | { |
| 106 | u32 reg = sun4i_spi_read(sspi, SUN4I_FIFO_STA_REG); |
| 107 | |
| 108 | reg >>= SUN4I_FIFO_STA_TF_CNT_BITS; |
| 109 | |
| 110 | return reg & SUN4I_FIFO_STA_TF_CNT_MASK; |
| 111 | } |
| 112 | |
| 113 | static inline void sun4i_spi_enable_interrupt(struct sun4i_spi *sspi, u32 mask) |
| 114 | { |
| 115 | u32 reg = sun4i_spi_read(sspi, SUN4I_INT_CTL_REG); |
| 116 | |
| 117 | reg |= mask; |
| 118 | sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, reg); |
| 119 | } |
| 120 | |
| 121 | static inline void sun4i_spi_disable_interrupt(struct sun4i_spi *sspi, u32 mask) |
| 122 | { |
| 123 | u32 reg = sun4i_spi_read(sspi, SUN4I_INT_CTL_REG); |
| 124 | |
| 125 | reg &= ~mask; |
| 126 | sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, reg); |
| 127 | } |
| 128 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 129 | static inline void sun4i_spi_drain_fifo(struct sun4i_spi *sspi, int len) |
| 130 | { |
| 131 | u32 reg, cnt; |
| 132 | u8 byte; |
| 133 | |
| 134 | /* See how much data is available */ |
| 135 | reg = sun4i_spi_read(sspi, SUN4I_FIFO_STA_REG); |
| 136 | reg &= SUN4I_FIFO_STA_RF_CNT_MASK; |
| 137 | cnt = reg >> SUN4I_FIFO_STA_RF_CNT_BITS; |
| 138 | |
| 139 | if (len > cnt) |
| 140 | len = cnt; |
| 141 | |
| 142 | while (len--) { |
| 143 | byte = readb(sspi->base_addr + SUN4I_RXDATA_REG); |
| 144 | if (sspi->rx_buf) |
| 145 | *sspi->rx_buf++ = byte; |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | static inline void sun4i_spi_fill_fifo(struct sun4i_spi *sspi, int len) |
| 150 | { |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 151 | u32 cnt; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 152 | u8 byte; |
| 153 | |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 154 | /* See how much data we can fit */ |
| 155 | cnt = SUN4I_FIFO_DEPTH - sun4i_spi_get_tx_fifo_count(sspi); |
| 156 | |
| 157 | len = min3(len, (int)cnt, sspi->len); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 158 | |
| 159 | while (len--) { |
| 160 | byte = sspi->tx_buf ? *sspi->tx_buf++ : 0; |
| 161 | writeb(byte, sspi->base_addr + SUN4I_TXDATA_REG); |
| 162 | sspi->len--; |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | static void sun4i_spi_set_cs(struct spi_device *spi, bool enable) |
| 167 | { |
| 168 | struct sun4i_spi *sspi = spi_master_get_devdata(spi->master); |
| 169 | u32 reg; |
| 170 | |
| 171 | reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); |
| 172 | |
| 173 | reg &= ~SUN4I_CTL_CS_MASK; |
| 174 | reg |= SUN4I_CTL_CS(spi->chip_select); |
| 175 | |
Marcus Weseloh | 218e0b5 | 2016-01-05 21:46:20 +0100 | [diff] [blame] | 176 | /* We want to control the chip select manually */ |
| 177 | reg |= SUN4I_CTL_CS_MANUAL; |
| 178 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 179 | if (enable) |
| 180 | reg |= SUN4I_CTL_CS_LEVEL; |
| 181 | else |
| 182 | reg &= ~SUN4I_CTL_CS_LEVEL; |
| 183 | |
| 184 | /* |
| 185 | * Even though this looks irrelevant since we are supposed to |
| 186 | * be controlling the chip select manually, this bit also |
| 187 | * controls the levels of the chip select for inactive |
| 188 | * devices. |
| 189 | * |
| 190 | * If we don't set it, the chip select level will go low by |
| 191 | * default when the device is idle, which is not really |
| 192 | * expected in the common case where the chip select is active |
| 193 | * low. |
| 194 | */ |
| 195 | if (spi->mode & SPI_CS_HIGH) |
| 196 | reg &= ~SUN4I_CTL_CS_ACTIVE_LOW; |
| 197 | else |
| 198 | reg |= SUN4I_CTL_CS_ACTIVE_LOW; |
| 199 | |
| 200 | sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); |
| 201 | } |
| 202 | |
Michal Suchanek | 794912c | 2016-06-13 17:46:50 +0000 | [diff] [blame] | 203 | static size_t sun4i_spi_max_transfer_size(struct spi_device *spi) |
| 204 | { |
| 205 | return SUN4I_FIFO_DEPTH - 1; |
| 206 | } |
| 207 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 208 | static int sun4i_spi_transfer_one(struct spi_master *master, |
| 209 | struct spi_device *spi, |
| 210 | struct spi_transfer *tfr) |
| 211 | { |
| 212 | struct sun4i_spi *sspi = spi_master_get_devdata(master); |
| 213 | unsigned int mclk_rate, div, timeout; |
Michal Suchanek | 719bd65 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 214 | unsigned int start, end, tx_time; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 215 | unsigned int tx_len = 0; |
| 216 | int ret = 0; |
| 217 | u32 reg; |
| 218 | |
| 219 | /* We don't support transfer larger than the FIFO */ |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 220 | if (tfr->len > SUN4I_MAX_XFER_SIZE) |
Michal Suchanek | 6d9fe44 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 221 | return -EMSGSIZE; |
| 222 | |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 223 | if (tfr->tx_buf && tfr->len >= SUN4I_MAX_XFER_SIZE) |
Michal Suchanek | 6d9fe44 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 224 | return -EMSGSIZE; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 225 | |
| 226 | reinit_completion(&sspi->done); |
| 227 | sspi->tx_buf = tfr->tx_buf; |
| 228 | sspi->rx_buf = tfr->rx_buf; |
| 229 | sspi->len = tfr->len; |
| 230 | |
| 231 | /* Clear pending interrupts */ |
| 232 | sun4i_spi_write(sspi, SUN4I_INT_STA_REG, ~0); |
| 233 | |
| 234 | |
| 235 | reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); |
| 236 | |
| 237 | /* Reset FIFOs */ |
| 238 | sun4i_spi_write(sspi, SUN4I_CTL_REG, |
| 239 | reg | SUN4I_CTL_RF_RST | SUN4I_CTL_TF_RST); |
| 240 | |
| 241 | /* |
| 242 | * Setup the transfer control register: Chip Select, |
| 243 | * polarities, etc. |
| 244 | */ |
| 245 | if (spi->mode & SPI_CPOL) |
| 246 | reg |= SUN4I_CTL_CPOL; |
| 247 | else |
| 248 | reg &= ~SUN4I_CTL_CPOL; |
| 249 | |
| 250 | if (spi->mode & SPI_CPHA) |
| 251 | reg |= SUN4I_CTL_CPHA; |
| 252 | else |
| 253 | reg &= ~SUN4I_CTL_CPHA; |
| 254 | |
| 255 | if (spi->mode & SPI_LSB_FIRST) |
| 256 | reg |= SUN4I_CTL_LMTF; |
| 257 | else |
| 258 | reg &= ~SUN4I_CTL_LMTF; |
| 259 | |
| 260 | |
| 261 | /* |
| 262 | * If it's a TX only transfer, we don't want to fill the RX |
| 263 | * FIFO with bogus data |
| 264 | */ |
| 265 | if (sspi->rx_buf) |
| 266 | reg &= ~SUN4I_CTL_DHB; |
| 267 | else |
| 268 | reg |= SUN4I_CTL_DHB; |
| 269 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 270 | sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); |
| 271 | |
| 272 | /* Ensure that we have a parent clock fast enough */ |
| 273 | mclk_rate = clk_get_rate(sspi->mclk); |
Marcus Weseloh | 47284e3 | 2015-11-08 12:03:23 +0100 | [diff] [blame] | 274 | if (mclk_rate < (2 * tfr->speed_hz)) { |
| 275 | clk_set_rate(sspi->mclk, 2 * tfr->speed_hz); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 276 | mclk_rate = clk_get_rate(sspi->mclk); |
| 277 | } |
| 278 | |
| 279 | /* |
| 280 | * Setup clock divider. |
| 281 | * |
| 282 | * We have two choices there. Either we can use the clock |
| 283 | * divide rate 1, which is calculated thanks to this formula: |
| 284 | * SPI_CLK = MOD_CLK / (2 ^ (cdr + 1)) |
| 285 | * Or we can use CDR2, which is calculated with the formula: |
| 286 | * SPI_CLK = MOD_CLK / (2 * (cdr + 1)) |
| 287 | * Wether we use the former or the latter is set through the |
| 288 | * DRS bit. |
| 289 | * |
| 290 | * First try CDR2, and if we can't reach the expected |
| 291 | * frequency, fall back to CDR1. |
| 292 | */ |
Marcus Weseloh | 47284e3 | 2015-11-08 12:03:23 +0100 | [diff] [blame] | 293 | div = mclk_rate / (2 * tfr->speed_hz); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 294 | if (div <= (SUN4I_CLK_CTL_CDR2_MASK + 1)) { |
| 295 | if (div > 0) |
| 296 | div--; |
| 297 | |
| 298 | reg = SUN4I_CLK_CTL_CDR2(div) | SUN4I_CLK_CTL_DRS; |
| 299 | } else { |
Marcus Weseloh | 47284e3 | 2015-11-08 12:03:23 +0100 | [diff] [blame] | 300 | div = ilog2(mclk_rate) - ilog2(tfr->speed_hz); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 301 | reg = SUN4I_CLK_CTL_CDR1(div); |
| 302 | } |
| 303 | |
| 304 | sun4i_spi_write(sspi, SUN4I_CLK_CTL_REG, reg); |
| 305 | |
| 306 | /* Setup the transfer now... */ |
| 307 | if (sspi->tx_buf) |
| 308 | tx_len = tfr->len; |
| 309 | |
| 310 | /* Setup the counters */ |
| 311 | sun4i_spi_write(sspi, SUN4I_BURST_CNT_REG, SUN4I_BURST_CNT(tfr->len)); |
| 312 | sun4i_spi_write(sspi, SUN4I_XMIT_CNT_REG, SUN4I_XMIT_CNT(tx_len)); |
| 313 | |
Michal Suchanek | 6d9fe44 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 314 | /* |
| 315 | * Fill the TX FIFO |
| 316 | * Filling the FIFO fully causes timeout for some reason |
| 317 | * at least on spi2 on A10s |
| 318 | */ |
| 319 | sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH - 1); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 320 | |
| 321 | /* Enable the interrupts */ |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 322 | sun4i_spi_enable_interrupt(sspi, SUN4I_INT_CTL_TC | |
| 323 | SUN4I_INT_CTL_RF_F34); |
| 324 | /* Only enable Tx FIFO interrupt if we really need it */ |
| 325 | if (tx_len > SUN4I_FIFO_DEPTH) |
| 326 | sun4i_spi_enable_interrupt(sspi, SUN4I_INT_CTL_TF_E34); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 327 | |
| 328 | /* Start the transfer */ |
| 329 | reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); |
| 330 | sun4i_spi_write(sspi, SUN4I_CTL_REG, reg | SUN4I_CTL_XCH); |
| 331 | |
Michal Suchanek | 719bd65 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 332 | tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U); |
| 333 | start = jiffies; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 334 | timeout = wait_for_completion_timeout(&sspi->done, |
Michal Suchanek | 719bd65 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 335 | msecs_to_jiffies(tx_time)); |
| 336 | end = jiffies; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 337 | if (!timeout) { |
Michal Suchanek | 719bd65 | 2016-06-13 17:46:49 +0000 | [diff] [blame] | 338 | dev_warn(&master->dev, |
| 339 | "%s: timeout transferring %u bytes@%iHz for %i(%i)ms", |
| 340 | dev_name(&spi->dev), tfr->len, tfr->speed_hz, |
| 341 | jiffies_to_msecs(end - start), tx_time); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 342 | ret = -ETIMEDOUT; |
| 343 | goto out; |
| 344 | } |
| 345 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 346 | |
| 347 | out: |
| 348 | sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, 0); |
| 349 | |
| 350 | return ret; |
| 351 | } |
| 352 | |
| 353 | static irqreturn_t sun4i_spi_handler(int irq, void *dev_id) |
| 354 | { |
| 355 | struct sun4i_spi *sspi = dev_id; |
| 356 | u32 status = sun4i_spi_read(sspi, SUN4I_INT_STA_REG); |
| 357 | |
| 358 | /* Transfer complete */ |
| 359 | if (status & SUN4I_INT_CTL_TC) { |
| 360 | sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_TC); |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 361 | sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 362 | complete(&sspi->done); |
| 363 | return IRQ_HANDLED; |
| 364 | } |
| 365 | |
Alexandru Gagniuc | 1967379 | 2016-10-26 00:00:31 -0700 | [diff] [blame] | 366 | /* Receive FIFO 3/4 full */ |
| 367 | if (status & SUN4I_INT_CTL_RF_F34) { |
| 368 | sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH); |
| 369 | /* Only clear the interrupt _after_ draining the FIFO */ |
| 370 | sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_RF_F34); |
| 371 | return IRQ_HANDLED; |
| 372 | } |
| 373 | |
| 374 | /* Transmit FIFO 3/4 empty */ |
| 375 | if (status & SUN4I_INT_CTL_TF_E34) { |
| 376 | sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH); |
| 377 | |
| 378 | if (!sspi->len) |
| 379 | /* nothing left to transmit */ |
| 380 | sun4i_spi_disable_interrupt(sspi, SUN4I_INT_CTL_TF_E34); |
| 381 | |
| 382 | /* Only clear the interrupt _after_ re-seeding the FIFO */ |
| 383 | sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_TF_E34); |
| 384 | |
| 385 | return IRQ_HANDLED; |
| 386 | } |
| 387 | |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 388 | return IRQ_NONE; |
| 389 | } |
| 390 | |
| 391 | static int sun4i_spi_runtime_resume(struct device *dev) |
| 392 | { |
| 393 | struct spi_master *master = dev_get_drvdata(dev); |
| 394 | struct sun4i_spi *sspi = spi_master_get_devdata(master); |
| 395 | int ret; |
| 396 | |
| 397 | ret = clk_prepare_enable(sspi->hclk); |
| 398 | if (ret) { |
| 399 | dev_err(dev, "Couldn't enable AHB clock\n"); |
| 400 | goto out; |
| 401 | } |
| 402 | |
| 403 | ret = clk_prepare_enable(sspi->mclk); |
| 404 | if (ret) { |
| 405 | dev_err(dev, "Couldn't enable module clock\n"); |
| 406 | goto err; |
| 407 | } |
| 408 | |
| 409 | sun4i_spi_write(sspi, SUN4I_CTL_REG, |
| 410 | SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER | SUN4I_CTL_TP); |
| 411 | |
| 412 | return 0; |
| 413 | |
| 414 | err: |
| 415 | clk_disable_unprepare(sspi->hclk); |
| 416 | out: |
| 417 | return ret; |
| 418 | } |
| 419 | |
| 420 | static int sun4i_spi_runtime_suspend(struct device *dev) |
| 421 | { |
| 422 | struct spi_master *master = dev_get_drvdata(dev); |
| 423 | struct sun4i_spi *sspi = spi_master_get_devdata(master); |
| 424 | |
| 425 | clk_disable_unprepare(sspi->mclk); |
| 426 | clk_disable_unprepare(sspi->hclk); |
| 427 | |
| 428 | return 0; |
| 429 | } |
| 430 | |
| 431 | static int sun4i_spi_probe(struct platform_device *pdev) |
| 432 | { |
| 433 | struct spi_master *master; |
| 434 | struct sun4i_spi *sspi; |
| 435 | struct resource *res; |
| 436 | int ret = 0, irq; |
| 437 | |
| 438 | master = spi_alloc_master(&pdev->dev, sizeof(struct sun4i_spi)); |
| 439 | if (!master) { |
| 440 | dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); |
| 441 | return -ENOMEM; |
| 442 | } |
| 443 | |
| 444 | platform_set_drvdata(pdev, master); |
| 445 | sspi = spi_master_get_devdata(master); |
| 446 | |
| 447 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 448 | sspi->base_addr = devm_ioremap_resource(&pdev->dev, res); |
| 449 | if (IS_ERR(sspi->base_addr)) { |
| 450 | ret = PTR_ERR(sspi->base_addr); |
| 451 | goto err_free_master; |
| 452 | } |
| 453 | |
| 454 | irq = platform_get_irq(pdev, 0); |
| 455 | if (irq < 0) { |
| 456 | dev_err(&pdev->dev, "No spi IRQ specified\n"); |
| 457 | ret = -ENXIO; |
| 458 | goto err_free_master; |
| 459 | } |
| 460 | |
| 461 | ret = devm_request_irq(&pdev->dev, irq, sun4i_spi_handler, |
| 462 | 0, "sun4i-spi", sspi); |
| 463 | if (ret) { |
| 464 | dev_err(&pdev->dev, "Cannot request IRQ\n"); |
| 465 | goto err_free_master; |
| 466 | } |
| 467 | |
| 468 | sspi->master = master; |
Michal Suchanek | 0b06d8c | 2016-06-14 12:10:04 +0000 | [diff] [blame] | 469 | master->max_speed_hz = 100 * 1000 * 1000; |
| 470 | master->min_speed_hz = 3 * 1000; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 471 | master->set_cs = sun4i_spi_set_cs; |
| 472 | master->transfer_one = sun4i_spi_transfer_one; |
| 473 | master->num_chipselect = 4; |
| 474 | master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; |
Axel Lin | ba47644 | 2014-03-02 22:25:10 +0800 | [diff] [blame] | 475 | master->bits_per_word_mask = SPI_BPW_MASK(8); |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 476 | master->dev.of_node = pdev->dev.of_node; |
| 477 | master->auto_runtime_pm = true; |
Michal Suchanek | 794912c | 2016-06-13 17:46:50 +0000 | [diff] [blame] | 478 | master->max_transfer_size = sun4i_spi_max_transfer_size; |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 479 | |
| 480 | sspi->hclk = devm_clk_get(&pdev->dev, "ahb"); |
| 481 | if (IS_ERR(sspi->hclk)) { |
| 482 | dev_err(&pdev->dev, "Unable to acquire AHB clock\n"); |
| 483 | ret = PTR_ERR(sspi->hclk); |
| 484 | goto err_free_master; |
| 485 | } |
| 486 | |
| 487 | sspi->mclk = devm_clk_get(&pdev->dev, "mod"); |
| 488 | if (IS_ERR(sspi->mclk)) { |
| 489 | dev_err(&pdev->dev, "Unable to acquire module clock\n"); |
| 490 | ret = PTR_ERR(sspi->mclk); |
| 491 | goto err_free_master; |
| 492 | } |
| 493 | |
| 494 | init_completion(&sspi->done); |
| 495 | |
| 496 | /* |
| 497 | * This wake-up/shutdown pattern is to be able to have the |
| 498 | * device woken up, even if runtime_pm is disabled |
| 499 | */ |
| 500 | ret = sun4i_spi_runtime_resume(&pdev->dev); |
| 501 | if (ret) { |
| 502 | dev_err(&pdev->dev, "Couldn't resume the device\n"); |
| 503 | goto err_free_master; |
| 504 | } |
| 505 | |
| 506 | pm_runtime_set_active(&pdev->dev); |
| 507 | pm_runtime_enable(&pdev->dev); |
| 508 | pm_runtime_idle(&pdev->dev); |
| 509 | |
| 510 | ret = devm_spi_register_master(&pdev->dev, master); |
| 511 | if (ret) { |
| 512 | dev_err(&pdev->dev, "cannot register SPI master\n"); |
| 513 | goto err_pm_disable; |
| 514 | } |
| 515 | |
| 516 | return 0; |
| 517 | |
| 518 | err_pm_disable: |
| 519 | pm_runtime_disable(&pdev->dev); |
| 520 | sun4i_spi_runtime_suspend(&pdev->dev); |
| 521 | err_free_master: |
| 522 | spi_master_put(master); |
| 523 | return ret; |
| 524 | } |
| 525 | |
| 526 | static int sun4i_spi_remove(struct platform_device *pdev) |
| 527 | { |
| 528 | pm_runtime_disable(&pdev->dev); |
| 529 | |
| 530 | return 0; |
| 531 | } |
| 532 | |
| 533 | static const struct of_device_id sun4i_spi_match[] = { |
| 534 | { .compatible = "allwinner,sun4i-a10-spi", }, |
| 535 | {} |
| 536 | }; |
| 537 | MODULE_DEVICE_TABLE(of, sun4i_spi_match); |
| 538 | |
| 539 | static const struct dev_pm_ops sun4i_spi_pm_ops = { |
| 540 | .runtime_resume = sun4i_spi_runtime_resume, |
| 541 | .runtime_suspend = sun4i_spi_runtime_suspend, |
| 542 | }; |
| 543 | |
| 544 | static struct platform_driver sun4i_spi_driver = { |
| 545 | .probe = sun4i_spi_probe, |
| 546 | .remove = sun4i_spi_remove, |
| 547 | .driver = { |
| 548 | .name = "sun4i-spi", |
Maxime Ripard | b5f6517 | 2014-02-22 22:35:53 +0100 | [diff] [blame] | 549 | .of_match_table = sun4i_spi_match, |
| 550 | .pm = &sun4i_spi_pm_ops, |
| 551 | }, |
| 552 | }; |
| 553 | module_platform_driver(sun4i_spi_driver); |
| 554 | |
| 555 | MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>"); |
| 556 | MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); |
| 557 | MODULE_DESCRIPTION("Allwinner A1X/A20 SPI controller driver"); |
| 558 | MODULE_LICENSE("GPL"); |