1ca632f55SGrant Likely /* 2ca632f55SGrant Likely * MPC52xx SPI bus driver. 3ca632f55SGrant Likely * 4ca632f55SGrant Likely * Copyright (C) 2008 Secret Lab Technologies Ltd. 5ca632f55SGrant Likely * 6ca632f55SGrant Likely * This file is released under the GPLv2 7ca632f55SGrant Likely * 8ca632f55SGrant Likely * This is the driver for the MPC5200's dedicated SPI controller. 9ca632f55SGrant Likely * 10ca632f55SGrant Likely * Note: this driver does not support the MPC5200 PSC in SPI mode. For 11ca632f55SGrant Likely * that driver see drivers/spi/mpc52xx_psc_spi.c 12ca632f55SGrant Likely */ 13ca632f55SGrant Likely 14ca632f55SGrant Likely #include <linux/module.h> 15ca632f55SGrant Likely #include <linux/init.h> 16ca632f55SGrant Likely #include <linux/errno.h> 17ca632f55SGrant Likely #include <linux/of_platform.h> 18ca632f55SGrant Likely #include <linux/interrupt.h> 19ca632f55SGrant Likely #include <linux/delay.h> 20ca632f55SGrant Likely #include <linux/spi/spi.h> 21ca632f55SGrant Likely #include <linux/io.h> 22ca632f55SGrant Likely #include <linux/of_gpio.h> 23ca632f55SGrant Likely #include <linux/slab.h> 24ca632f55SGrant Likely #include <asm/time.h> 25ca632f55SGrant Likely #include <asm/mpc52xx.h> 26ca632f55SGrant Likely 27ca632f55SGrant Likely MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 28ca632f55SGrant Likely MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver"); 29ca632f55SGrant Likely MODULE_LICENSE("GPL"); 30ca632f55SGrant Likely 31ca632f55SGrant Likely /* Register offsets */ 32ca632f55SGrant Likely #define SPI_CTRL1 0x00 33ca632f55SGrant Likely #define SPI_CTRL1_SPIE (1 << 7) 34ca632f55SGrant Likely #define SPI_CTRL1_SPE (1 << 6) 35ca632f55SGrant Likely #define SPI_CTRL1_MSTR (1 << 4) 36ca632f55SGrant Likely #define SPI_CTRL1_CPOL (1 << 3) 37ca632f55SGrant Likely #define SPI_CTRL1_CPHA (1 << 2) 38ca632f55SGrant Likely #define SPI_CTRL1_SSOE (1 << 1) 39ca632f55SGrant Likely #define SPI_CTRL1_LSBFE (1 << 0) 40ca632f55SGrant Likely 41ca632f55SGrant Likely #define SPI_CTRL2 0x01 42ca632f55SGrant Likely #define SPI_BRR 0x04 43ca632f55SGrant Likely 44ca632f55SGrant Likely #define SPI_STATUS 0x05 45ca632f55SGrant Likely #define SPI_STATUS_SPIF (1 << 7) 46ca632f55SGrant Likely #define SPI_STATUS_WCOL (1 << 6) 47ca632f55SGrant Likely #define SPI_STATUS_MODF (1 << 4) 48ca632f55SGrant Likely 49ca632f55SGrant Likely #define SPI_DATA 0x09 50ca632f55SGrant Likely #define SPI_PORTDATA 0x0d 51ca632f55SGrant Likely #define SPI_DATADIR 0x10 52ca632f55SGrant Likely 53ca632f55SGrant Likely /* FSM state return values */ 54ca632f55SGrant Likely #define FSM_STOP 0 /* Nothing more for the state machine to */ 55ca632f55SGrant Likely /* do. If something interesting happens */ 56ca632f55SGrant Likely /* then an IRQ will be received */ 57ca632f55SGrant Likely #define FSM_POLL 1 /* need to poll for completion, an IRQ is */ 58ca632f55SGrant Likely /* not expected */ 59ca632f55SGrant Likely #define FSM_CONTINUE 2 /* Keep iterating the state machine */ 60ca632f55SGrant Likely 61ca632f55SGrant Likely /* Driver internal data */ 62ca632f55SGrant Likely struct mpc52xx_spi { 63ca632f55SGrant Likely struct spi_master *master; 64ca632f55SGrant Likely void __iomem *regs; 65ca632f55SGrant Likely int irq0; /* MODF irq */ 66ca632f55SGrant Likely int irq1; /* SPIF irq */ 67ca632f55SGrant Likely unsigned int ipb_freq; 68ca632f55SGrant Likely 69ca632f55SGrant Likely /* Statistics; not used now, but will be reintroduced for debugfs */ 70ca632f55SGrant Likely int msg_count; 71ca632f55SGrant Likely int wcol_count; 72ca632f55SGrant Likely int wcol_ticks; 73ca632f55SGrant Likely u32 wcol_tx_timestamp; 74ca632f55SGrant Likely int modf_count; 75ca632f55SGrant Likely int byte_count; 76ca632f55SGrant Likely 77ca632f55SGrant Likely struct list_head queue; /* queue of pending messages */ 78ca632f55SGrant Likely spinlock_t lock; 79ca632f55SGrant Likely struct work_struct work; 80ca632f55SGrant Likely 81ca632f55SGrant Likely /* Details of current transfer (length, and buffer pointers) */ 82ca632f55SGrant Likely struct spi_message *message; /* current message */ 83ca632f55SGrant Likely struct spi_transfer *transfer; /* current transfer */ 84ca632f55SGrant Likely int (*state)(int irq, struct mpc52xx_spi *ms, u8 status, u8 data); 85ca632f55SGrant Likely int len; 86ca632f55SGrant Likely int timestamp; 87ca632f55SGrant Likely u8 *rx_buf; 88ca632f55SGrant Likely const u8 *tx_buf; 89ca632f55SGrant Likely int cs_change; 90ca632f55SGrant Likely int gpio_cs_count; 91ca632f55SGrant Likely unsigned int *gpio_cs; 92ca632f55SGrant Likely }; 93ca632f55SGrant Likely 94ca632f55SGrant Likely /* 95ca632f55SGrant Likely * CS control function 96ca632f55SGrant Likely */ 97ca632f55SGrant Likely static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value) 98ca632f55SGrant Likely { 99ca632f55SGrant Likely int cs; 100ca632f55SGrant Likely 101ca632f55SGrant Likely if (ms->gpio_cs_count > 0) { 102ca632f55SGrant Likely cs = ms->message->spi->chip_select; 103ca632f55SGrant Likely gpio_set_value(ms->gpio_cs[cs], value ? 0 : 1); 104ca632f55SGrant Likely } else 105ca632f55SGrant Likely out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08); 106ca632f55SGrant Likely } 107ca632f55SGrant Likely 108ca632f55SGrant Likely /* 109ca632f55SGrant Likely * Start a new transfer. This is called both by the idle state 110ca632f55SGrant Likely * for the first transfer in a message, and by the wait state when the 111ca632f55SGrant Likely * previous transfer in a message is complete. 112ca632f55SGrant Likely */ 113ca632f55SGrant Likely static void mpc52xx_spi_start_transfer(struct mpc52xx_spi *ms) 114ca632f55SGrant Likely { 115ca632f55SGrant Likely ms->rx_buf = ms->transfer->rx_buf; 116ca632f55SGrant Likely ms->tx_buf = ms->transfer->tx_buf; 117ca632f55SGrant Likely ms->len = ms->transfer->len; 118ca632f55SGrant Likely 119ca632f55SGrant Likely /* Activate the chip select */ 120ca632f55SGrant Likely if (ms->cs_change) 121ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 1); 122ca632f55SGrant Likely ms->cs_change = ms->transfer->cs_change; 123ca632f55SGrant Likely 124ca632f55SGrant Likely /* Write out the first byte */ 125ca632f55SGrant Likely ms->wcol_tx_timestamp = get_tbl(); 126ca632f55SGrant Likely if (ms->tx_buf) 127ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, *ms->tx_buf++); 128ca632f55SGrant Likely else 129ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, 0); 130ca632f55SGrant Likely } 131ca632f55SGrant Likely 132ca632f55SGrant Likely /* Forward declaration of state handlers */ 133ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, 134ca632f55SGrant Likely u8 status, u8 data); 135ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, 136ca632f55SGrant Likely u8 status, u8 data); 137ca632f55SGrant Likely 138ca632f55SGrant Likely /* 139ca632f55SGrant Likely * IDLE state 140ca632f55SGrant Likely * 141ca632f55SGrant Likely * No transfers are in progress; if another transfer is pending then retrieve 142ca632f55SGrant Likely * it and kick it off. Otherwise, stop processing the state machine 143ca632f55SGrant Likely */ 144ca632f55SGrant Likely static int 145ca632f55SGrant Likely mpc52xx_spi_fsmstate_idle(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) 146ca632f55SGrant Likely { 147ca632f55SGrant Likely struct spi_device *spi; 148ca632f55SGrant Likely int spr, sppr; 149ca632f55SGrant Likely u8 ctrl1; 150ca632f55SGrant Likely 151ca632f55SGrant Likely if (status && (irq != NO_IRQ)) 152ca632f55SGrant Likely dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", 153ca632f55SGrant Likely status); 154ca632f55SGrant Likely 155ca632f55SGrant Likely /* Check if there is another transfer waiting. */ 156ca632f55SGrant Likely if (list_empty(&ms->queue)) 157ca632f55SGrant Likely return FSM_STOP; 158ca632f55SGrant Likely 159ca632f55SGrant Likely /* get the head of the queue */ 160ca632f55SGrant Likely ms->message = list_first_entry(&ms->queue, struct spi_message, queue); 161ca632f55SGrant Likely list_del_init(&ms->message->queue); 162ca632f55SGrant Likely 163ca632f55SGrant Likely /* Setup the controller parameters */ 164ca632f55SGrant Likely ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; 165ca632f55SGrant Likely spi = ms->message->spi; 166ca632f55SGrant Likely if (spi->mode & SPI_CPHA) 167ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_CPHA; 168ca632f55SGrant Likely if (spi->mode & SPI_CPOL) 169ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_CPOL; 170ca632f55SGrant Likely if (spi->mode & SPI_LSB_FIRST) 171ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_LSBFE; 172ca632f55SGrant Likely out_8(ms->regs + SPI_CTRL1, ctrl1); 173ca632f55SGrant Likely 174ca632f55SGrant Likely /* Setup the controller speed */ 175ca632f55SGrant Likely /* minimum divider is '2'. Also, add '1' to force rounding the 176ca632f55SGrant Likely * divider up. */ 177ca632f55SGrant Likely sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1; 178ca632f55SGrant Likely spr = 0; 179ca632f55SGrant Likely if (sppr < 1) 180ca632f55SGrant Likely sppr = 1; 181ca632f55SGrant Likely while (((sppr - 1) & ~0x7) != 0) { 182ca632f55SGrant Likely sppr = (sppr + 1) >> 1; /* add '1' to force rounding up */ 183ca632f55SGrant Likely spr++; 184ca632f55SGrant Likely } 185ca632f55SGrant Likely sppr--; /* sppr quantity in register is offset by 1 */ 186ca632f55SGrant Likely if (spr > 7) { 187ca632f55SGrant Likely /* Don't overrun limits of SPI baudrate register */ 188ca632f55SGrant Likely spr = 7; 189ca632f55SGrant Likely sppr = 7; 190ca632f55SGrant Likely } 191ca632f55SGrant Likely out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */ 192ca632f55SGrant Likely 193ca632f55SGrant Likely ms->cs_change = 1; 194ca632f55SGrant Likely ms->transfer = container_of(ms->message->transfers.next, 195ca632f55SGrant Likely struct spi_transfer, transfer_list); 196ca632f55SGrant Likely 197ca632f55SGrant Likely mpc52xx_spi_start_transfer(ms); 198ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_transfer; 199ca632f55SGrant Likely 200ca632f55SGrant Likely return FSM_CONTINUE; 201ca632f55SGrant Likely } 202ca632f55SGrant Likely 203ca632f55SGrant Likely /* 204ca632f55SGrant Likely * TRANSFER state 205ca632f55SGrant Likely * 206ca632f55SGrant Likely * In the middle of a transfer. If the SPI core has completed processing 207ca632f55SGrant Likely * a byte, then read out the received data and write out the next byte 208ca632f55SGrant Likely * (unless this transfer is finished; in which case go on to the wait 209ca632f55SGrant Likely * state) 210ca632f55SGrant Likely */ 211ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, 212ca632f55SGrant Likely u8 status, u8 data) 213ca632f55SGrant Likely { 214ca632f55SGrant Likely if (!status) 215ca632f55SGrant Likely return ms->irq0 ? FSM_STOP : FSM_POLL; 216ca632f55SGrant Likely 217ca632f55SGrant Likely if (status & SPI_STATUS_WCOL) { 218ca632f55SGrant Likely /* The SPI controller is stoopid. At slower speeds, it may 219ca632f55SGrant Likely * raise the SPIF flag before the state machine is actually 220ca632f55SGrant Likely * finished, which causes a collision (internal to the state 221ca632f55SGrant Likely * machine only). The manual recommends inserting a delay 222ca632f55SGrant Likely * between receiving the interrupt and sending the next byte, 223ca632f55SGrant Likely * but it can also be worked around simply by retrying the 224ca632f55SGrant Likely * transfer which is what we do here. */ 225ca632f55SGrant Likely ms->wcol_count++; 226ca632f55SGrant Likely ms->wcol_ticks += get_tbl() - ms->wcol_tx_timestamp; 227ca632f55SGrant Likely ms->wcol_tx_timestamp = get_tbl(); 228ca632f55SGrant Likely data = 0; 229ca632f55SGrant Likely if (ms->tx_buf) 230ca632f55SGrant Likely data = *(ms->tx_buf - 1); 231ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, data); /* try again */ 232ca632f55SGrant Likely return FSM_CONTINUE; 233ca632f55SGrant Likely } else if (status & SPI_STATUS_MODF) { 234ca632f55SGrant Likely ms->modf_count++; 235ca632f55SGrant Likely dev_err(&ms->master->dev, "mode fault\n"); 236ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 237ca632f55SGrant Likely ms->message->status = -EIO; 238ca632f55SGrant Likely ms->message->complete(ms->message->context); 239ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 240ca632f55SGrant Likely return FSM_CONTINUE; 241ca632f55SGrant Likely } 242ca632f55SGrant Likely 243ca632f55SGrant Likely /* Read data out of the spi device */ 244ca632f55SGrant Likely ms->byte_count++; 245ca632f55SGrant Likely if (ms->rx_buf) 246ca632f55SGrant Likely *ms->rx_buf++ = data; 247ca632f55SGrant Likely 248ca632f55SGrant Likely /* Is the transfer complete? */ 249ca632f55SGrant Likely ms->len--; 250ca632f55SGrant Likely if (ms->len == 0) { 251ca632f55SGrant Likely ms->timestamp = get_tbl(); 252ca632f55SGrant Likely ms->timestamp += ms->transfer->delay_usecs * tb_ticks_per_usec; 253ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_wait; 254ca632f55SGrant Likely return FSM_CONTINUE; 255ca632f55SGrant Likely } 256ca632f55SGrant Likely 257ca632f55SGrant Likely /* Write out the next byte */ 258ca632f55SGrant Likely ms->wcol_tx_timestamp = get_tbl(); 259ca632f55SGrant Likely if (ms->tx_buf) 260ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, *ms->tx_buf++); 261ca632f55SGrant Likely else 262ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, 0); 263ca632f55SGrant Likely 264ca632f55SGrant Likely return FSM_CONTINUE; 265ca632f55SGrant Likely } 266ca632f55SGrant Likely 267ca632f55SGrant Likely /* 268ca632f55SGrant Likely * WAIT state 269ca632f55SGrant Likely * 270ca632f55SGrant Likely * A transfer has completed; need to wait for the delay period to complete 271ca632f55SGrant Likely * before starting the next transfer 272ca632f55SGrant Likely */ 273ca632f55SGrant Likely static int 274ca632f55SGrant Likely mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) 275ca632f55SGrant Likely { 276ca632f55SGrant Likely if (status && irq) 277ca632f55SGrant Likely dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", 278ca632f55SGrant Likely status); 279ca632f55SGrant Likely 280ca632f55SGrant Likely if (((int)get_tbl()) - ms->timestamp < 0) 281ca632f55SGrant Likely return FSM_POLL; 282ca632f55SGrant Likely 283ca632f55SGrant Likely ms->message->actual_length += ms->transfer->len; 284ca632f55SGrant Likely 285ca632f55SGrant Likely /* Check if there is another transfer in this message. If there 286ca632f55SGrant Likely * aren't then deactivate CS, notify sender, and drop back to idle 287ca632f55SGrant Likely * to start the next message. */ 288ca632f55SGrant Likely if (ms->transfer->transfer_list.next == &ms->message->transfers) { 289ca632f55SGrant Likely ms->msg_count++; 290ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 291ca632f55SGrant Likely ms->message->status = 0; 292ca632f55SGrant Likely ms->message->complete(ms->message->context); 293ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 294ca632f55SGrant Likely return FSM_CONTINUE; 295ca632f55SGrant Likely } 296ca632f55SGrant Likely 297ca632f55SGrant Likely /* There is another transfer; kick it off */ 298ca632f55SGrant Likely 299ca632f55SGrant Likely if (ms->cs_change) 300ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 301ca632f55SGrant Likely 302ca632f55SGrant Likely ms->transfer = container_of(ms->transfer->transfer_list.next, 303ca632f55SGrant Likely struct spi_transfer, transfer_list); 304ca632f55SGrant Likely mpc52xx_spi_start_transfer(ms); 305ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_transfer; 306ca632f55SGrant Likely return FSM_CONTINUE; 307ca632f55SGrant Likely } 308ca632f55SGrant Likely 309ca632f55SGrant Likely /** 310ca632f55SGrant Likely * mpc52xx_spi_fsm_process - Finite State Machine iteration function 311ca632f55SGrant Likely * @irq: irq number that triggered the FSM or 0 for polling 312ca632f55SGrant Likely * @ms: pointer to mpc52xx_spi driver data 313ca632f55SGrant Likely */ 314ca632f55SGrant Likely static void mpc52xx_spi_fsm_process(int irq, struct mpc52xx_spi *ms) 315ca632f55SGrant Likely { 316ca632f55SGrant Likely int rc = FSM_CONTINUE; 317ca632f55SGrant Likely u8 status, data; 318ca632f55SGrant Likely 319ca632f55SGrant Likely while (rc == FSM_CONTINUE) { 320ca632f55SGrant Likely /* Interrupt cleared by read of STATUS followed by 321ca632f55SGrant Likely * read of DATA registers */ 322ca632f55SGrant Likely status = in_8(ms->regs + SPI_STATUS); 323ca632f55SGrant Likely data = in_8(ms->regs + SPI_DATA); 324ca632f55SGrant Likely rc = ms->state(irq, ms, status, data); 325ca632f55SGrant Likely } 326ca632f55SGrant Likely 327ca632f55SGrant Likely if (rc == FSM_POLL) 328ca632f55SGrant Likely schedule_work(&ms->work); 329ca632f55SGrant Likely } 330ca632f55SGrant Likely 331ca632f55SGrant Likely /** 332ca632f55SGrant Likely * mpc52xx_spi_irq - IRQ handler 333ca632f55SGrant Likely */ 334ca632f55SGrant Likely static irqreturn_t mpc52xx_spi_irq(int irq, void *_ms) 335ca632f55SGrant Likely { 336ca632f55SGrant Likely struct mpc52xx_spi *ms = _ms; 337ca632f55SGrant Likely spin_lock(&ms->lock); 338ca632f55SGrant Likely mpc52xx_spi_fsm_process(irq, ms); 339ca632f55SGrant Likely spin_unlock(&ms->lock); 340ca632f55SGrant Likely return IRQ_HANDLED; 341ca632f55SGrant Likely } 342ca632f55SGrant Likely 343ca632f55SGrant Likely /** 344ca632f55SGrant Likely * mpc52xx_spi_wq - Workqueue function for polling the state machine 345ca632f55SGrant Likely */ 346ca632f55SGrant Likely static void mpc52xx_spi_wq(struct work_struct *work) 347ca632f55SGrant Likely { 348ca632f55SGrant Likely struct mpc52xx_spi *ms = container_of(work, struct mpc52xx_spi, work); 349ca632f55SGrant Likely unsigned long flags; 350ca632f55SGrant Likely 351ca632f55SGrant Likely spin_lock_irqsave(&ms->lock, flags); 352ca632f55SGrant Likely mpc52xx_spi_fsm_process(0, ms); 353ca632f55SGrant Likely spin_unlock_irqrestore(&ms->lock, flags); 354ca632f55SGrant Likely } 355ca632f55SGrant Likely 356ca632f55SGrant Likely /* 357ca632f55SGrant Likely * spi_master ops 358ca632f55SGrant Likely */ 359ca632f55SGrant Likely 360ca632f55SGrant Likely static int mpc52xx_spi_setup(struct spi_device *spi) 361ca632f55SGrant Likely { 362ca632f55SGrant Likely if (spi->bits_per_word % 8) 363ca632f55SGrant Likely return -EINVAL; 364ca632f55SGrant Likely 365ca632f55SGrant Likely if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) 366ca632f55SGrant Likely return -EINVAL; 367ca632f55SGrant Likely 368ca632f55SGrant Likely if (spi->chip_select >= spi->master->num_chipselect) 369ca632f55SGrant Likely return -EINVAL; 370ca632f55SGrant Likely 371ca632f55SGrant Likely return 0; 372ca632f55SGrant Likely } 373ca632f55SGrant Likely 374ca632f55SGrant Likely static int mpc52xx_spi_transfer(struct spi_device *spi, struct spi_message *m) 375ca632f55SGrant Likely { 376ca632f55SGrant Likely struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master); 377ca632f55SGrant Likely unsigned long flags; 378ca632f55SGrant Likely 379ca632f55SGrant Likely m->actual_length = 0; 380ca632f55SGrant Likely m->status = -EINPROGRESS; 381ca632f55SGrant Likely 382ca632f55SGrant Likely spin_lock_irqsave(&ms->lock, flags); 383ca632f55SGrant Likely list_add_tail(&m->queue, &ms->queue); 384ca632f55SGrant Likely spin_unlock_irqrestore(&ms->lock, flags); 385ca632f55SGrant Likely schedule_work(&ms->work); 386ca632f55SGrant Likely 387ca632f55SGrant Likely return 0; 388ca632f55SGrant Likely } 389ca632f55SGrant Likely 390ca632f55SGrant Likely /* 391ca632f55SGrant Likely * OF Platform Bus Binding 392ca632f55SGrant Likely */ 393fd4a319bSGrant Likely static int mpc52xx_spi_probe(struct platform_device *op) 394ca632f55SGrant Likely { 395ca632f55SGrant Likely struct spi_master *master; 396ca632f55SGrant Likely struct mpc52xx_spi *ms; 397ca632f55SGrant Likely void __iomem *regs; 398ca632f55SGrant Likely u8 ctrl1; 399ca632f55SGrant Likely int rc, i = 0; 400ca632f55SGrant Likely int gpio_cs; 401ca632f55SGrant Likely 402ca632f55SGrant Likely /* MMIO registers */ 403ca632f55SGrant Likely dev_dbg(&op->dev, "probing mpc5200 SPI device\n"); 404ca632f55SGrant Likely regs = of_iomap(op->dev.of_node, 0); 405ca632f55SGrant Likely if (!regs) 406ca632f55SGrant Likely return -ENODEV; 407ca632f55SGrant Likely 408ca632f55SGrant Likely /* initialize the device */ 409ca632f55SGrant Likely ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; 410ca632f55SGrant Likely out_8(regs + SPI_CTRL1, ctrl1); 411ca632f55SGrant Likely out_8(regs + SPI_CTRL2, 0x0); 412ca632f55SGrant Likely out_8(regs + SPI_DATADIR, 0xe); /* Set output pins */ 413ca632f55SGrant Likely out_8(regs + SPI_PORTDATA, 0x8); /* Deassert /SS signal */ 414ca632f55SGrant Likely 415ca632f55SGrant Likely /* Clear the status register and re-read it to check for a MODF 416ca632f55SGrant Likely * failure. This driver cannot currently handle multiple masters 417ca632f55SGrant Likely * on the SPI bus. This fault will also occur if the SPI signals 418ca632f55SGrant Likely * are not connected to any pins (port_config setting) */ 419ca632f55SGrant Likely in_8(regs + SPI_STATUS); 420ca632f55SGrant Likely out_8(regs + SPI_CTRL1, ctrl1); 421ca632f55SGrant Likely 422ca632f55SGrant Likely in_8(regs + SPI_DATA); 423ca632f55SGrant Likely if (in_8(regs + SPI_STATUS) & SPI_STATUS_MODF) { 424ca632f55SGrant Likely dev_err(&op->dev, "mode fault; is port_config correct?\n"); 425ca632f55SGrant Likely rc = -EIO; 426ca632f55SGrant Likely goto err_init; 427ca632f55SGrant Likely } 428ca632f55SGrant Likely 429ca632f55SGrant Likely dev_dbg(&op->dev, "allocating spi_master struct\n"); 430ca632f55SGrant Likely master = spi_alloc_master(&op->dev, sizeof *ms); 431ca632f55SGrant Likely if (!master) { 432ca632f55SGrant Likely rc = -ENOMEM; 433ca632f55SGrant Likely goto err_alloc; 434ca632f55SGrant Likely } 435ca632f55SGrant Likely 436ca632f55SGrant Likely master->setup = mpc52xx_spi_setup; 437ca632f55SGrant Likely master->transfer = mpc52xx_spi_transfer; 438ca632f55SGrant Likely master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; 439ca632f55SGrant Likely master->dev.of_node = op->dev.of_node; 440ca632f55SGrant Likely 44124b5a82cSJingoo Han platform_set_drvdata(op, master); 442ca632f55SGrant Likely 443ca632f55SGrant Likely ms = spi_master_get_devdata(master); 444ca632f55SGrant Likely ms->master = master; 445ca632f55SGrant Likely ms->regs = regs; 446ca632f55SGrant Likely ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0); 447ca632f55SGrant Likely ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1); 448ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 449ca632f55SGrant Likely ms->ipb_freq = mpc5xxx_get_bus_frequency(op->dev.of_node); 450ca632f55SGrant Likely ms->gpio_cs_count = of_gpio_count(op->dev.of_node); 451ca632f55SGrant Likely if (ms->gpio_cs_count > 0) { 452ca632f55SGrant Likely master->num_chipselect = ms->gpio_cs_count; 453ca632f55SGrant Likely ms->gpio_cs = kmalloc(ms->gpio_cs_count * sizeof(unsigned int), 454ca632f55SGrant Likely GFP_KERNEL); 455ca632f55SGrant Likely if (!ms->gpio_cs) { 456ca632f55SGrant Likely rc = -ENOMEM; 457866c0f25SGuenter Roeck goto err_alloc_gpio; 458ca632f55SGrant Likely } 459ca632f55SGrant Likely 460ca632f55SGrant Likely for (i = 0; i < ms->gpio_cs_count; i++) { 461ca632f55SGrant Likely gpio_cs = of_get_gpio(op->dev.of_node, i); 462ca632f55SGrant Likely if (gpio_cs < 0) { 463ca632f55SGrant Likely dev_err(&op->dev, 464ca632f55SGrant Likely "could not parse the gpio field " 465ca632f55SGrant Likely "in oftree\n"); 466ca632f55SGrant Likely rc = -ENODEV; 467ca632f55SGrant Likely goto err_gpio; 468ca632f55SGrant Likely } 469ca632f55SGrant Likely 470ca632f55SGrant Likely rc = gpio_request(gpio_cs, dev_name(&op->dev)); 471ca632f55SGrant Likely if (rc) { 472ca632f55SGrant Likely dev_err(&op->dev, 473ca632f55SGrant Likely "can't request spi cs gpio #%d " 474ca632f55SGrant Likely "on gpio line %d\n", i, gpio_cs); 475ca632f55SGrant Likely goto err_gpio; 476ca632f55SGrant Likely } 477ca632f55SGrant Likely 478ca632f55SGrant Likely gpio_direction_output(gpio_cs, 1); 479ca632f55SGrant Likely ms->gpio_cs[i] = gpio_cs; 480ca632f55SGrant Likely } 481ca632f55SGrant Likely } 482ca632f55SGrant Likely 483ca632f55SGrant Likely spin_lock_init(&ms->lock); 484ca632f55SGrant Likely INIT_LIST_HEAD(&ms->queue); 485ca632f55SGrant Likely INIT_WORK(&ms->work, mpc52xx_spi_wq); 486ca632f55SGrant Likely 487ca632f55SGrant Likely /* Decide if interrupts can be used */ 488ca632f55SGrant Likely if (ms->irq0 && ms->irq1) { 489ca632f55SGrant Likely rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0, 490ca632f55SGrant Likely "mpc5200-spi-modf", ms); 491ca632f55SGrant Likely rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0, 492ca632f55SGrant Likely "mpc5200-spi-spif", ms); 493ca632f55SGrant Likely if (rc) { 494ca632f55SGrant Likely free_irq(ms->irq0, ms); 495ca632f55SGrant Likely free_irq(ms->irq1, ms); 496ca632f55SGrant Likely ms->irq0 = ms->irq1 = 0; 497ca632f55SGrant Likely } 498ca632f55SGrant Likely } else { 499ca632f55SGrant Likely /* operate in polled mode */ 500ca632f55SGrant Likely ms->irq0 = ms->irq1 = 0; 501ca632f55SGrant Likely } 502ca632f55SGrant Likely 503ca632f55SGrant Likely if (!ms->irq0) 504ca632f55SGrant Likely dev_info(&op->dev, "using polled mode\n"); 505ca632f55SGrant Likely 506ca632f55SGrant Likely dev_dbg(&op->dev, "registering spi_master struct\n"); 507ca632f55SGrant Likely rc = spi_register_master(master); 508ca632f55SGrant Likely if (rc) 509ca632f55SGrant Likely goto err_register; 510ca632f55SGrant Likely 511ca632f55SGrant Likely dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n"); 512ca632f55SGrant Likely 513ca632f55SGrant Likely return rc; 514ca632f55SGrant Likely 515ca632f55SGrant Likely err_register: 516ca632f55SGrant Likely dev_err(&ms->master->dev, "initialization failed\n"); 517ca632f55SGrant Likely err_gpio: 518ca632f55SGrant Likely while (i-- > 0) 519ca632f55SGrant Likely gpio_free(ms->gpio_cs[i]); 520ca632f55SGrant Likely 521ca632f55SGrant Likely kfree(ms->gpio_cs); 522866c0f25SGuenter Roeck err_alloc_gpio: 523866c0f25SGuenter Roeck spi_master_put(master); 524ca632f55SGrant Likely err_alloc: 525ca632f55SGrant Likely err_init: 526ca632f55SGrant Likely iounmap(regs); 527ca632f55SGrant Likely return rc; 528ca632f55SGrant Likely } 529ca632f55SGrant Likely 530fd4a319bSGrant Likely static int mpc52xx_spi_remove(struct platform_device *op) 531ca632f55SGrant Likely { 53224b5a82cSJingoo Han struct spi_master *master = spi_master_get(platform_get_drvdata(op)); 533ca632f55SGrant Likely struct mpc52xx_spi *ms = spi_master_get_devdata(master); 534ca632f55SGrant Likely int i; 535ca632f55SGrant Likely 536ca632f55SGrant Likely free_irq(ms->irq0, ms); 537ca632f55SGrant Likely free_irq(ms->irq1, ms); 538ca632f55SGrant Likely 539ca632f55SGrant Likely for (i = 0; i < ms->gpio_cs_count; i++) 540ca632f55SGrant Likely gpio_free(ms->gpio_cs[i]); 541ca632f55SGrant Likely 542ca632f55SGrant Likely kfree(ms->gpio_cs); 543ca632f55SGrant Likely spi_unregister_master(master); 544ca632f55SGrant Likely iounmap(ms->regs); 545f95e1028SGuenter Roeck spi_master_put(master); 546ca632f55SGrant Likely 547ca632f55SGrant Likely return 0; 548ca632f55SGrant Likely } 549ca632f55SGrant Likely 550fd4a319bSGrant Likely static const struct of_device_id mpc52xx_spi_match[] = { 551ca632f55SGrant Likely { .compatible = "fsl,mpc5200-spi", }, 552ca632f55SGrant Likely {} 553ca632f55SGrant Likely }; 554ca632f55SGrant Likely MODULE_DEVICE_TABLE(of, mpc52xx_spi_match); 555ca632f55SGrant Likely 556ca632f55SGrant Likely static struct platform_driver mpc52xx_spi_of_driver = { 557ca632f55SGrant Likely .driver = { 558ca632f55SGrant Likely .name = "mpc52xx-spi", 559ca632f55SGrant Likely .owner = THIS_MODULE, 560ca632f55SGrant Likely .of_match_table = mpc52xx_spi_match, 561ca632f55SGrant Likely }, 562ca632f55SGrant Likely .probe = mpc52xx_spi_probe, 563fd4a319bSGrant Likely .remove = mpc52xx_spi_remove, 564ca632f55SGrant Likely }; 565940ab889SGrant Likely module_platform_driver(mpc52xx_spi_of_driver); 566