Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 1 | /* |
| 2 | * MPC83xx SPI controller driver. |
| 3 | * |
| 4 | * Maintainer: Kumar Gala |
| 5 | * |
| 6 | * Copyright (C) 2006 Polycom, Inc. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License as published by the |
| 10 | * Free Software Foundation; either version 2 of the License, or (at your |
| 11 | * option) any later version. |
| 12 | */ |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/types.h> |
| 16 | #include <linux/kernel.h> |
| 17 | #include <linux/completion.h> |
| 18 | #include <linux/interrupt.h> |
| 19 | #include <linux/delay.h> |
| 20 | #include <linux/irq.h> |
| 21 | #include <linux/device.h> |
| 22 | #include <linux/spi/spi.h> |
| 23 | #include <linux/spi/spi_bitbang.h> |
| 24 | #include <linux/platform_device.h> |
| 25 | #include <linux/fsl_devices.h> |
| 26 | |
| 27 | #include <asm/irq.h> |
| 28 | #include <asm/io.h> |
| 29 | |
| 30 | /* SPI Controller registers */ |
| 31 | struct mpc83xx_spi_reg { |
| 32 | u8 res1[0x20]; |
| 33 | __be32 mode; |
| 34 | __be32 event; |
| 35 | __be32 mask; |
| 36 | __be32 command; |
| 37 | __be32 transmit; |
| 38 | __be32 receive; |
| 39 | }; |
| 40 | |
| 41 | /* SPI Controller mode register definitions */ |
Anton Vorontsov | 2a485d7 | 2007-07-31 00:38:45 -0700 | [diff] [blame] | 42 | #define SPMODE_LOOP (1 << 30) |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 43 | #define SPMODE_CI_INACTIVEHIGH (1 << 29) |
| 44 | #define SPMODE_CP_BEGIN_EDGECLK (1 << 28) |
| 45 | #define SPMODE_DIV16 (1 << 27) |
| 46 | #define SPMODE_REV (1 << 26) |
| 47 | #define SPMODE_MS (1 << 25) |
| 48 | #define SPMODE_ENABLE (1 << 24) |
| 49 | #define SPMODE_LEN(x) ((x) << 20) |
| 50 | #define SPMODE_PM(x) ((x) << 16) |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 51 | #define SPMODE_OP (1 << 14) |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 52 | #define SPMODE_CG(x) ((x) << 7) |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 53 | |
| 54 | /* |
| 55 | * Default for SPI Mode: |
| 56 | * SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk |
| 57 | */ |
| 58 | #define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \ |
| 59 | SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf)) |
| 60 | |
| 61 | /* SPIE register values */ |
| 62 | #define SPIE_NE 0x00000200 /* Not empty */ |
| 63 | #define SPIE_NF 0x00000100 /* Not full */ |
| 64 | |
| 65 | /* SPIM register values */ |
| 66 | #define SPIM_NE 0x00000200 /* Not empty */ |
| 67 | #define SPIM_NF 0x00000100 /* Not full */ |
| 68 | |
| 69 | /* SPI Controller driver's private data. */ |
| 70 | struct mpc83xx_spi { |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 71 | struct mpc83xx_spi_reg __iomem *base; |
| 72 | |
| 73 | /* rx & tx bufs from the spi_transfer */ |
| 74 | const void *tx; |
| 75 | void *rx; |
| 76 | |
| 77 | /* functions to deal with different sized buffers */ |
| 78 | void (*get_rx) (u32 rx_data, struct mpc83xx_spi *); |
| 79 | u32(*get_tx) (struct mpc83xx_spi *); |
| 80 | |
| 81 | unsigned int count; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 82 | int irq; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 83 | |
| 84 | unsigned nsecs; /* (clock cycle time)/2 */ |
| 85 | |
Anton Vorontsov | e24a4d1 | 2007-08-10 13:01:01 -0700 | [diff] [blame] | 86 | u32 spibrg; /* SPIBRG input clock */ |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 87 | u32 rx_shift; /* RX data reg shift when in qe mode */ |
| 88 | u32 tx_shift; /* TX data reg shift when in qe mode */ |
| 89 | |
| 90 | bool qe_mode; |
| 91 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 92 | void (*activate_cs) (u8 cs, u8 polarity); |
| 93 | void (*deactivate_cs) (u8 cs, u8 polarity); |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 94 | |
| 95 | u8 busy; |
| 96 | |
| 97 | struct workqueue_struct *workqueue; |
| 98 | struct work_struct work; |
| 99 | |
| 100 | struct list_head queue; |
| 101 | spinlock_t lock; |
| 102 | |
| 103 | struct completion done; |
| 104 | }; |
| 105 | |
| 106 | struct spi_mpc83xx_cs { |
| 107 | /* functions to deal with different sized buffers */ |
| 108 | void (*get_rx) (u32 rx_data, struct mpc83xx_spi *); |
| 109 | u32 (*get_tx) (struct mpc83xx_spi *); |
| 110 | u32 rx_shift; /* RX data reg shift when in qe mode */ |
| 111 | u32 tx_shift; /* TX data reg shift when in qe mode */ |
| 112 | u32 hw_mode; /* Holds HW mode register settings */ |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 113 | }; |
| 114 | |
| 115 | static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val) |
| 116 | { |
| 117 | out_be32(reg, val); |
| 118 | } |
| 119 | |
| 120 | static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg) |
| 121 | { |
| 122 | return in_be32(reg); |
| 123 | } |
| 124 | |
| 125 | #define MPC83XX_SPI_RX_BUF(type) \ |
| 126 | void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \ |
| 127 | { \ |
| 128 | type * rx = mpc83xx_spi->rx; \ |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 129 | *rx++ = (type)(data >> mpc83xx_spi->rx_shift); \ |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 130 | mpc83xx_spi->rx = rx; \ |
| 131 | } |
| 132 | |
| 133 | #define MPC83XX_SPI_TX_BUF(type) \ |
| 134 | u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi) \ |
| 135 | { \ |
| 136 | u32 data; \ |
| 137 | const type * tx = mpc83xx_spi->tx; \ |
David Brownell | 4b1badf | 2006-12-29 16:48:39 -0800 | [diff] [blame] | 138 | if (!tx) \ |
| 139 | return 0; \ |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 140 | data = *tx++ << mpc83xx_spi->tx_shift; \ |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 141 | mpc83xx_spi->tx = tx; \ |
| 142 | return data; \ |
| 143 | } |
| 144 | |
| 145 | MPC83XX_SPI_RX_BUF(u8) |
| 146 | MPC83XX_SPI_RX_BUF(u16) |
| 147 | MPC83XX_SPI_RX_BUF(u32) |
| 148 | MPC83XX_SPI_TX_BUF(u8) |
| 149 | MPC83XX_SPI_TX_BUF(u16) |
| 150 | MPC83XX_SPI_TX_BUF(u32) |
| 151 | |
| 152 | static void mpc83xx_spi_chipselect(struct spi_device *spi, int value) |
| 153 | { |
| 154 | struct mpc83xx_spi *mpc83xx_spi; |
| 155 | u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 156 | struct spi_mpc83xx_cs *cs = spi->controller_state; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 157 | |
| 158 | mpc83xx_spi = spi_master_get_devdata(spi->master); |
| 159 | |
| 160 | if (value == BITBANG_CS_INACTIVE) { |
| 161 | if (mpc83xx_spi->deactivate_cs) |
| 162 | mpc83xx_spi->deactivate_cs(spi->chip_select, pol); |
| 163 | } |
| 164 | |
| 165 | if (value == BITBANG_CS_ACTIVE) { |
| 166 | u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); |
Anton Vorontsov | a44648b | 2007-08-10 13:01:02 -0700 | [diff] [blame] | 167 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 168 | mpc83xx_spi->rx_shift = cs->rx_shift; |
| 169 | mpc83xx_spi->tx_shift = cs->tx_shift; |
| 170 | mpc83xx_spi->get_rx = cs->get_rx; |
| 171 | mpc83xx_spi->get_tx = cs->get_tx; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 172 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 173 | if (cs->hw_mode != regval) { |
| 174 | unsigned long flags; |
| 175 | void *tmp_ptr = &mpc83xx_spi->base->mode; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 176 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 177 | regval = cs->hw_mode; |
| 178 | /* Turn off IRQs locally to minimize time that |
| 179 | * SPI is disabled |
| 180 | */ |
| 181 | local_irq_save(flags); |
| 182 | /* Turn off SPI unit prior changing mode */ |
| 183 | mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE); |
| 184 | mpc83xx_spi_write_reg(tmp_ptr, regval); |
| 185 | local_irq_restore(flags); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 186 | } |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 187 | if (mpc83xx_spi->activate_cs) |
| 188 | mpc83xx_spi->activate_cs(spi->chip_select, pol); |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | static |
| 193 | int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) |
| 194 | { |
| 195 | struct mpc83xx_spi *mpc83xx_spi; |
| 196 | u32 regval; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 197 | u8 bits_per_word, pm; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 198 | u32 hz; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 199 | struct spi_mpc83xx_cs *cs = spi->controller_state; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 200 | |
| 201 | mpc83xx_spi = spi_master_get_devdata(spi->master); |
| 202 | |
| 203 | if (t) { |
| 204 | bits_per_word = t->bits_per_word; |
| 205 | hz = t->speed_hz; |
| 206 | } else { |
| 207 | bits_per_word = 0; |
| 208 | hz = 0; |
| 209 | } |
| 210 | |
| 211 | /* spi_transfer level calls that work per-word */ |
| 212 | if (!bits_per_word) |
| 213 | bits_per_word = spi->bits_per_word; |
| 214 | |
| 215 | /* Make sure its a bit width we support [4..16, 32] */ |
| 216 | if ((bits_per_word < 4) |
| 217 | || ((bits_per_word > 16) && (bits_per_word != 32))) |
| 218 | return -EINVAL; |
| 219 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 220 | if (!hz) |
| 221 | hz = spi->max_speed_hz; |
| 222 | |
| 223 | cs->rx_shift = 0; |
| 224 | cs->tx_shift = 0; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 225 | if (bits_per_word <= 8) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 226 | cs->get_rx = mpc83xx_spi_rx_buf_u8; |
| 227 | cs->get_tx = mpc83xx_spi_tx_buf_u8; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 228 | if (mpc83xx_spi->qe_mode) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 229 | cs->rx_shift = 16; |
| 230 | cs->tx_shift = 24; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 231 | } |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 232 | } else if (bits_per_word <= 16) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 233 | cs->get_rx = mpc83xx_spi_rx_buf_u16; |
| 234 | cs->get_tx = mpc83xx_spi_tx_buf_u16; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 235 | if (mpc83xx_spi->qe_mode) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 236 | cs->rx_shift = 16; |
| 237 | cs->tx_shift = 16; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 238 | } |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 239 | } else if (bits_per_word <= 32) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 240 | cs->get_rx = mpc83xx_spi_rx_buf_u32; |
| 241 | cs->get_tx = mpc83xx_spi_tx_buf_u32; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 242 | } else |
| 243 | return -EINVAL; |
| 244 | |
Anton Vorontsov | 35cc0b9 | 2007-07-31 00:38:42 -0700 | [diff] [blame] | 245 | if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) { |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 246 | cs->tx_shift = 0; |
Anton Vorontsov | 35cc0b9 | 2007-07-31 00:38:42 -0700 | [diff] [blame] | 247 | if (bits_per_word <= 8) |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 248 | cs->rx_shift = 8; |
Anton Vorontsov | 35cc0b9 | 2007-07-31 00:38:42 -0700 | [diff] [blame] | 249 | else |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 250 | cs->rx_shift = 0; |
Anton Vorontsov | 35cc0b9 | 2007-07-31 00:38:42 -0700 | [diff] [blame] | 251 | } |
| 252 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 253 | mpc83xx_spi->rx_shift = cs->rx_shift; |
| 254 | mpc83xx_spi->tx_shift = cs->tx_shift; |
| 255 | mpc83xx_spi->get_rx = cs->get_rx; |
| 256 | mpc83xx_spi->get_tx = cs->get_tx; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 257 | |
| 258 | if (bits_per_word == 32) |
| 259 | bits_per_word = 0; |
| 260 | else |
| 261 | bits_per_word = bits_per_word - 1; |
| 262 | |
Anton Vorontsov | 32421da | 2007-07-31 00:38:41 -0700 | [diff] [blame] | 263 | /* mask out bits we are going to set */ |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 264 | cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16 |
| 265 | | SPMODE_PM(0xF)); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 266 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 267 | cs->hw_mode |= SPMODE_LEN(bits_per_word); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 268 | |
Chen Gong | a61f534 | 2008-07-23 21:29:52 -0700 | [diff] [blame] | 269 | if ((mpc83xx_spi->spibrg / hz) > 64) { |
Peter Korsgaard | 53604db | 2008-09-13 02:33:14 -0700 | [diff] [blame] | 270 | cs->hw_mode |= SPMODE_DIV16; |
Chen Gong | a61f534 | 2008-07-23 21:29:52 -0700 | [diff] [blame] | 271 | pm = mpc83xx_spi->spibrg / (hz * 64); |
| 272 | if (pm > 16) { |
Peter Korsgaard | 53604db | 2008-09-13 02:33:14 -0700 | [diff] [blame] | 273 | dev_err(&spi->dev, "Requested speed is too " |
| 274 | "low: %d Hz. Will use %d Hz instead.\n", |
| 275 | hz, mpc83xx_spi->spibrg / 1024); |
| 276 | pm = 16; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 277 | } |
Chen Gong | a61f534 | 2008-07-23 21:29:52 -0700 | [diff] [blame] | 278 | } else |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 279 | pm = mpc83xx_spi->spibrg / (hz * 4); |
Chen Gong | a61f534 | 2008-07-23 21:29:52 -0700 | [diff] [blame] | 280 | if (pm) |
| 281 | pm--; |
| 282 | |
| 283 | cs->hw_mode |= SPMODE_PM(pm); |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 284 | regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); |
| 285 | if (cs->hw_mode != regval) { |
| 286 | unsigned long flags; |
| 287 | void *tmp_ptr = &mpc83xx_spi->base->mode; |
David Brownell | dccd573 | 2007-07-17 04:04:02 -0700 | [diff] [blame] | 288 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 289 | regval = cs->hw_mode; |
| 290 | /* Turn off IRQs locally to minimize time |
| 291 | * that SPI is disabled |
| 292 | */ |
| 293 | local_irq_save(flags); |
| 294 | /* Turn off SPI unit prior changing mode */ |
| 295 | mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE); |
| 296 | mpc83xx_spi_write_reg(tmp_ptr, regval); |
| 297 | local_irq_restore(flags); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 298 | } |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 299 | return 0; |
| 300 | } |
| 301 | |
| 302 | static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t) |
| 303 | { |
| 304 | struct mpc83xx_spi *mpc83xx_spi; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 305 | u32 word, len, bits_per_word; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 306 | |
| 307 | mpc83xx_spi = spi_master_get_devdata(spi->master); |
| 308 | |
| 309 | mpc83xx_spi->tx = t->tx_buf; |
| 310 | mpc83xx_spi->rx = t->rx_buf; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 311 | bits_per_word = spi->bits_per_word; |
| 312 | if (t->bits_per_word) |
| 313 | bits_per_word = t->bits_per_word; |
| 314 | len = t->len; |
Peter Korsgaard | aa77d96 | 2008-09-13 02:33:15 -0700 | [diff] [blame] | 315 | if (bits_per_word > 8) { |
| 316 | /* invalid length? */ |
| 317 | if (len & 1) |
| 318 | return -EINVAL; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 319 | len /= 2; |
Peter Korsgaard | aa77d96 | 2008-09-13 02:33:15 -0700 | [diff] [blame] | 320 | } |
| 321 | if (bits_per_word > 16) { |
| 322 | /* invalid length? */ |
| 323 | if (len & 1) |
| 324 | return -EINVAL; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 325 | len /= 2; |
Peter Korsgaard | aa77d96 | 2008-09-13 02:33:15 -0700 | [diff] [blame] | 326 | } |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 327 | mpc83xx_spi->count = len; |
Peter Korsgaard | aa77d96 | 2008-09-13 02:33:15 -0700 | [diff] [blame] | 328 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 329 | INIT_COMPLETION(mpc83xx_spi->done); |
| 330 | |
| 331 | /* enable rx ints */ |
| 332 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE); |
| 333 | |
| 334 | /* transmit word */ |
| 335 | word = mpc83xx_spi->get_tx(mpc83xx_spi); |
| 336 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word); |
| 337 | |
| 338 | wait_for_completion(&mpc83xx_spi->done); |
| 339 | |
| 340 | /* disable rx ints */ |
| 341 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0); |
| 342 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 343 | return mpc83xx_spi->count; |
| 344 | } |
| 345 | |
| 346 | static void mpc83xx_spi_work(struct work_struct *work) |
| 347 | { |
| 348 | struct mpc83xx_spi *mpc83xx_spi = |
| 349 | container_of(work, struct mpc83xx_spi, work); |
| 350 | |
| 351 | spin_lock_irq(&mpc83xx_spi->lock); |
| 352 | mpc83xx_spi->busy = 1; |
| 353 | while (!list_empty(&mpc83xx_spi->queue)) { |
| 354 | struct spi_message *m; |
| 355 | struct spi_device *spi; |
| 356 | struct spi_transfer *t = NULL; |
| 357 | unsigned cs_change; |
| 358 | int status, nsecs = 50; |
| 359 | |
| 360 | m = container_of(mpc83xx_spi->queue.next, |
| 361 | struct spi_message, queue); |
| 362 | list_del_init(&m->queue); |
| 363 | spin_unlock_irq(&mpc83xx_spi->lock); |
| 364 | |
| 365 | spi = m->spi; |
| 366 | cs_change = 1; |
| 367 | status = 0; |
| 368 | list_for_each_entry(t, &m->transfers, transfer_list) { |
| 369 | if (t->bits_per_word || t->speed_hz) { |
| 370 | /* Don't allow changes if CS is active */ |
| 371 | status = -EINVAL; |
| 372 | |
| 373 | if (cs_change) |
| 374 | status = mpc83xx_spi_setup_transfer(spi, t); |
| 375 | if (status < 0) |
| 376 | break; |
| 377 | } |
| 378 | |
| 379 | if (cs_change) |
| 380 | mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE); |
| 381 | cs_change = t->cs_change; |
| 382 | if (t->len) |
| 383 | status = mpc83xx_spi_bufs(spi, t); |
| 384 | if (status) { |
| 385 | status = -EMSGSIZE; |
| 386 | break; |
| 387 | } |
| 388 | m->actual_length += t->len; |
| 389 | |
| 390 | if (t->delay_usecs) |
| 391 | udelay(t->delay_usecs); |
| 392 | |
| 393 | if (cs_change) { |
| 394 | ndelay(nsecs); |
| 395 | mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); |
| 396 | ndelay(nsecs); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | m->status = status; |
| 401 | m->complete(m->context); |
| 402 | |
| 403 | if (status || !cs_change) { |
| 404 | ndelay(nsecs); |
| 405 | mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); |
| 406 | } |
| 407 | |
| 408 | mpc83xx_spi_setup_transfer(spi, NULL); |
| 409 | |
| 410 | spin_lock_irq(&mpc83xx_spi->lock); |
| 411 | } |
| 412 | mpc83xx_spi->busy = 0; |
| 413 | spin_unlock_irq(&mpc83xx_spi->lock); |
| 414 | } |
| 415 | |
| 416 | /* the spi->mode bits understood by this driver: */ |
| 417 | #define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ |
| 418 | | SPI_LSB_FIRST | SPI_LOOP) |
| 419 | |
| 420 | static int mpc83xx_spi_setup(struct spi_device *spi) |
| 421 | { |
| 422 | struct mpc83xx_spi *mpc83xx_spi; |
| 423 | int retval; |
| 424 | u32 hw_mode; |
| 425 | struct spi_mpc83xx_cs *cs = spi->controller_state; |
| 426 | |
| 427 | if (spi->mode & ~MODEBITS) { |
| 428 | dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", |
| 429 | spi->mode & ~MODEBITS); |
| 430 | return -EINVAL; |
| 431 | } |
| 432 | |
| 433 | if (!spi->max_speed_hz) |
| 434 | return -EINVAL; |
| 435 | |
| 436 | if (!cs) { |
| 437 | cs = kzalloc(sizeof *cs, GFP_KERNEL); |
| 438 | if (!cs) |
| 439 | return -ENOMEM; |
| 440 | spi->controller_state = cs; |
| 441 | } |
| 442 | mpc83xx_spi = spi_master_get_devdata(spi->master); |
| 443 | |
| 444 | if (!spi->bits_per_word) |
| 445 | spi->bits_per_word = 8; |
| 446 | |
| 447 | hw_mode = cs->hw_mode; /* Save orginal settings */ |
| 448 | cs->hw_mode = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); |
| 449 | /* mask out bits we are going to set */ |
| 450 | cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH |
| 451 | | SPMODE_REV | SPMODE_LOOP); |
| 452 | |
| 453 | if (spi->mode & SPI_CPHA) |
| 454 | cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK; |
| 455 | if (spi->mode & SPI_CPOL) |
| 456 | cs->hw_mode |= SPMODE_CI_INACTIVEHIGH; |
| 457 | if (!(spi->mode & SPI_LSB_FIRST)) |
| 458 | cs->hw_mode |= SPMODE_REV; |
| 459 | if (spi->mode & SPI_LOOP) |
| 460 | cs->hw_mode |= SPMODE_LOOP; |
| 461 | |
| 462 | retval = mpc83xx_spi_setup_transfer(spi, NULL); |
| 463 | if (retval < 0) { |
| 464 | cs->hw_mode = hw_mode; /* Restore settings */ |
| 465 | return retval; |
| 466 | } |
| 467 | |
| 468 | dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u Hz\n", |
| 469 | __func__, spi->mode & (SPI_CPOL | SPI_CPHA), |
| 470 | spi->bits_per_word, spi->max_speed_hz); |
| 471 | #if 0 /* Don't think this is needed */ |
| 472 | /* NOTE we _need_ to call chipselect() early, ideally with adapter |
| 473 | * setup, unless the hardware defaults cooperate to avoid confusion |
| 474 | * between normal (active low) and inverted chipselects. |
| 475 | */ |
| 476 | |
| 477 | /* deselect chip (low or high) */ |
| 478 | spin_lock(&mpc83xx_spi->lock); |
| 479 | if (!mpc83xx_spi->busy) |
| 480 | mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE); |
| 481 | spin_unlock(&mpc83xx_spi->lock); |
| 482 | #endif |
| 483 | return 0; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 484 | } |
| 485 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 486 | irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data) |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 487 | { |
| 488 | struct mpc83xx_spi *mpc83xx_spi = context_data; |
| 489 | u32 event; |
| 490 | irqreturn_t ret = IRQ_NONE; |
| 491 | |
| 492 | /* Get interrupt events(tx/rx) */ |
| 493 | event = mpc83xx_spi_read_reg(&mpc83xx_spi->base->event); |
| 494 | |
| 495 | /* We need handle RX first */ |
| 496 | if (event & SPIE_NE) { |
| 497 | u32 rx_data = mpc83xx_spi_read_reg(&mpc83xx_spi->base->receive); |
| 498 | |
| 499 | if (mpc83xx_spi->rx) |
| 500 | mpc83xx_spi->get_rx(rx_data, mpc83xx_spi); |
| 501 | |
| 502 | ret = IRQ_HANDLED; |
| 503 | } |
| 504 | |
| 505 | if ((event & SPIE_NF) == 0) |
| 506 | /* spin until TX is done */ |
| 507 | while (((event = |
| 508 | mpc83xx_spi_read_reg(&mpc83xx_spi->base->event)) & |
| 509 | SPIE_NF) == 0) |
| 510 | cpu_relax(); |
| 511 | |
| 512 | mpc83xx_spi->count -= 1; |
| 513 | if (mpc83xx_spi->count) { |
Jan Andersson | 65e213c | 2007-09-11 15:23:30 -0700 | [diff] [blame] | 514 | u32 word = mpc83xx_spi->get_tx(mpc83xx_spi); |
| 515 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 516 | } else { |
| 517 | complete(&mpc83xx_spi->done); |
| 518 | } |
| 519 | |
| 520 | /* Clear the events */ |
| 521 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, event); |
| 522 | |
| 523 | return ret; |
| 524 | } |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 525 | static int mpc83xx_spi_transfer(struct spi_device *spi, |
| 526 | struct spi_message *m) |
| 527 | { |
| 528 | struct mpc83xx_spi *mpc83xx_spi = spi_master_get_devdata(spi->master); |
| 529 | unsigned long flags; |
| 530 | |
| 531 | m->actual_length = 0; |
| 532 | m->status = -EINPROGRESS; |
| 533 | |
| 534 | spin_lock_irqsave(&mpc83xx_spi->lock, flags); |
| 535 | list_add_tail(&m->queue, &mpc83xx_spi->queue); |
| 536 | queue_work(mpc83xx_spi->workqueue, &mpc83xx_spi->work); |
| 537 | spin_unlock_irqrestore(&mpc83xx_spi->lock, flags); |
| 538 | |
| 539 | return 0; |
| 540 | } |
| 541 | |
| 542 | |
| 543 | static void mpc83xx_spi_cleanup(struct spi_device *spi) |
| 544 | { |
| 545 | kfree(spi->controller_state); |
| 546 | } |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 547 | |
| 548 | static int __init mpc83xx_spi_probe(struct platform_device *dev) |
| 549 | { |
| 550 | struct spi_master *master; |
| 551 | struct mpc83xx_spi *mpc83xx_spi; |
| 552 | struct fsl_spi_platform_data *pdata; |
| 553 | struct resource *r; |
| 554 | u32 regval; |
| 555 | int ret = 0; |
| 556 | |
| 557 | /* Get resources(memory, IRQ) associated with the device */ |
| 558 | master = spi_alloc_master(&dev->dev, sizeof(struct mpc83xx_spi)); |
| 559 | |
| 560 | if (master == NULL) { |
| 561 | ret = -ENOMEM; |
| 562 | goto err; |
| 563 | } |
| 564 | |
| 565 | platform_set_drvdata(dev, master); |
| 566 | pdata = dev->dev.platform_data; |
| 567 | |
| 568 | if (pdata == NULL) { |
| 569 | ret = -ENODEV; |
| 570 | goto free_master; |
| 571 | } |
| 572 | |
| 573 | r = platform_get_resource(dev, IORESOURCE_MEM, 0); |
| 574 | if (r == NULL) { |
| 575 | ret = -ENODEV; |
| 576 | goto free_master; |
| 577 | } |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 578 | master->setup = mpc83xx_spi_setup; |
| 579 | master->transfer = mpc83xx_spi_transfer; |
| 580 | master->cleanup = mpc83xx_spi_cleanup; |
| 581 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 582 | mpc83xx_spi = spi_master_get_devdata(master); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 583 | mpc83xx_spi->activate_cs = pdata->activate_cs; |
| 584 | mpc83xx_spi->deactivate_cs = pdata->deactivate_cs; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 585 | mpc83xx_spi->qe_mode = pdata->qe_mode; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 586 | mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8; |
| 587 | mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8; |
Anton Vorontsov | 59a0ea5 | 2008-01-24 18:40:03 +0300 | [diff] [blame] | 588 | mpc83xx_spi->spibrg = pdata->sysclk; |
Anton Vorontsov | e24a4d1 | 2007-08-10 13:01:01 -0700 | [diff] [blame] | 589 | |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 590 | mpc83xx_spi->rx_shift = 0; |
| 591 | mpc83xx_spi->tx_shift = 0; |
| 592 | if (mpc83xx_spi->qe_mode) { |
| 593 | mpc83xx_spi->rx_shift = 16; |
| 594 | mpc83xx_spi->tx_shift = 24; |
| 595 | } |
| 596 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 597 | init_completion(&mpc83xx_spi->done); |
| 598 | |
| 599 | mpc83xx_spi->base = ioremap(r->start, r->end - r->start + 1); |
| 600 | if (mpc83xx_spi->base == NULL) { |
| 601 | ret = -ENOMEM; |
| 602 | goto put_master; |
| 603 | } |
| 604 | |
| 605 | mpc83xx_spi->irq = platform_get_irq(dev, 0); |
| 606 | |
| 607 | if (mpc83xx_spi->irq < 0) { |
| 608 | ret = -ENXIO; |
| 609 | goto unmap_io; |
| 610 | } |
| 611 | |
| 612 | /* Register for SPI Interrupt */ |
| 613 | ret = request_irq(mpc83xx_spi->irq, mpc83xx_spi_irq, |
| 614 | 0, "mpc83xx_spi", mpc83xx_spi); |
| 615 | |
| 616 | if (ret != 0) |
| 617 | goto unmap_io; |
| 618 | |
| 619 | master->bus_num = pdata->bus_num; |
| 620 | master->num_chipselect = pdata->max_chipselect; |
| 621 | |
| 622 | /* SPI controller initializations */ |
| 623 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0); |
| 624 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0); |
| 625 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->command, 0); |
| 626 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, 0xffffffff); |
| 627 | |
| 628 | /* Enable SPI interface */ |
| 629 | regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; |
Joakim Tjernlund | f29ba28 | 2007-07-17 04:04:12 -0700 | [diff] [blame] | 630 | if (pdata->qe_mode) |
| 631 | regval |= SPMODE_OP; |
| 632 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 633 | mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval); |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 634 | spin_lock_init(&mpc83xx_spi->lock); |
| 635 | init_completion(&mpc83xx_spi->done); |
| 636 | INIT_WORK(&mpc83xx_spi->work, mpc83xx_spi_work); |
| 637 | INIT_LIST_HEAD(&mpc83xx_spi->queue); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 638 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 639 | mpc83xx_spi->workqueue = create_singlethread_workqueue( |
| 640 | master->dev.parent->bus_id); |
| 641 | if (mpc83xx_spi->workqueue == NULL) { |
| 642 | ret = -EBUSY; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 643 | goto free_irq; |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 644 | } |
| 645 | |
| 646 | ret = spi_register_master(master); |
| 647 | if (ret < 0) |
| 648 | goto unreg_master; |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 649 | |
| 650 | printk(KERN_INFO |
| 651 | "%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n", |
| 652 | dev->dev.bus_id, mpc83xx_spi->base, mpc83xx_spi->irq); |
| 653 | |
| 654 | return ret; |
| 655 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 656 | unreg_master: |
| 657 | destroy_workqueue(mpc83xx_spi->workqueue); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 658 | free_irq: |
| 659 | free_irq(mpc83xx_spi->irq, mpc83xx_spi); |
| 660 | unmap_io: |
| 661 | iounmap(mpc83xx_spi->base); |
| 662 | put_master: |
| 663 | spi_master_put(master); |
| 664 | free_master: |
| 665 | kfree(master); |
| 666 | err: |
| 667 | return ret; |
| 668 | } |
| 669 | |
David Brownell | d1e44d9 | 2007-10-16 01:27:46 -0700 | [diff] [blame] | 670 | static int __exit mpc83xx_spi_remove(struct platform_device *dev) |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 671 | { |
| 672 | struct mpc83xx_spi *mpc83xx_spi; |
| 673 | struct spi_master *master; |
| 674 | |
| 675 | master = platform_get_drvdata(dev); |
| 676 | mpc83xx_spi = spi_master_get_devdata(master); |
| 677 | |
Joakim Tjernlund | c9bfcb3 | 2008-05-12 14:02:30 -0700 | [diff] [blame] | 678 | flush_workqueue(mpc83xx_spi->workqueue); |
| 679 | destroy_workqueue(mpc83xx_spi->workqueue); |
| 680 | spi_unregister_master(master); |
| 681 | |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 682 | free_irq(mpc83xx_spi->irq, mpc83xx_spi); |
| 683 | iounmap(mpc83xx_spi->base); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 684 | |
| 685 | return 0; |
| 686 | } |
| 687 | |
Kay Sievers | 7e38c3c | 2008-04-10 21:29:20 -0700 | [diff] [blame] | 688 | MODULE_ALIAS("platform:mpc83xx_spi"); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 689 | static struct platform_driver mpc83xx_spi_driver = { |
David Brownell | d1e44d9 | 2007-10-16 01:27:46 -0700 | [diff] [blame] | 690 | .remove = __exit_p(mpc83xx_spi_remove), |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 691 | .driver = { |
Kay Sievers | 7e38c3c | 2008-04-10 21:29:20 -0700 | [diff] [blame] | 692 | .name = "mpc83xx_spi", |
| 693 | .owner = THIS_MODULE, |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 694 | }, |
| 695 | }; |
| 696 | |
| 697 | static int __init mpc83xx_spi_init(void) |
| 698 | { |
David Brownell | d1e44d9 | 2007-10-16 01:27:46 -0700 | [diff] [blame] | 699 | return platform_driver_probe(&mpc83xx_spi_driver, mpc83xx_spi_probe); |
Kumar Gala | ccf0699 | 2006-05-20 15:00:15 -0700 | [diff] [blame] | 700 | } |
| 701 | |
| 702 | static void __exit mpc83xx_spi_exit(void) |
| 703 | { |
| 704 | platform_driver_unregister(&mpc83xx_spi_driver); |
| 705 | } |
| 706 | |
| 707 | module_init(mpc83xx_spi_init); |
| 708 | module_exit(mpc83xx_spi_exit); |
| 709 | |
| 710 | MODULE_AUTHOR("Kumar Gala"); |
| 711 | MODULE_DESCRIPTION("Simple MPC83xx SPI Driver"); |
| 712 | MODULE_LICENSE("GPL"); |