155716d26SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 2ca632f55SGrant Likely /* 3ca632f55SGrant Likely * MPC52xx SPI bus driver. 4ca632f55SGrant Likely * 5ca632f55SGrant Likely * Copyright (C) 2008 Secret Lab Technologies Ltd. 6ca632f55SGrant Likely * 7ca632f55SGrant Likely * This is the driver for the MPC5200's dedicated SPI controller. 8ca632f55SGrant Likely * 9ca632f55SGrant Likely * Note: this driver does not support the MPC5200 PSC in SPI mode. For 10ca632f55SGrant Likely * that driver see drivers/spi/mpc52xx_psc_spi.c 11ca632f55SGrant Likely */ 12ca632f55SGrant Likely 13ca632f55SGrant Likely #include <linux/module.h> 142f3a896bSDmitry Torokhov #include <linux/err.h> 15ca632f55SGrant Likely #include <linux/errno.h> 16ca632f55SGrant Likely #include <linux/of_platform.h> 17ca632f55SGrant Likely #include <linux/interrupt.h> 18ca632f55SGrant Likely #include <linux/delay.h> 19a0c4b120SAndy Shevchenko #include <linux/gpio/consumer.h> 20ca632f55SGrant Likely #include <linux/spi/spi.h> 21ca632f55SGrant Likely #include <linux/io.h> 22ca632f55SGrant Likely #include <linux/slab.h> 2302b30248SChristophe Leroy #include <linux/of_address.h> 2402b30248SChristophe Leroy #include <linux/of_irq.h> 2502b30248SChristophe Leroy 26ca632f55SGrant Likely #include <asm/time.h> 27ca632f55SGrant Likely #include <asm/mpc52xx.h> 28ca632f55SGrant Likely 29ca632f55SGrant Likely MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 30ca632f55SGrant Likely MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver"); 31ca632f55SGrant Likely MODULE_LICENSE("GPL"); 32ca632f55SGrant Likely 33ca632f55SGrant Likely /* Register offsets */ 34ca632f55SGrant Likely #define SPI_CTRL1 0x00 35ca632f55SGrant Likely #define SPI_CTRL1_SPIE (1 << 7) 36ca632f55SGrant Likely #define SPI_CTRL1_SPE (1 << 6) 37ca632f55SGrant Likely #define SPI_CTRL1_MSTR (1 << 4) 38ca632f55SGrant Likely #define SPI_CTRL1_CPOL (1 << 3) 39ca632f55SGrant Likely #define SPI_CTRL1_CPHA (1 << 2) 40ca632f55SGrant Likely #define SPI_CTRL1_SSOE (1 << 1) 41ca632f55SGrant Likely #define SPI_CTRL1_LSBFE (1 << 0) 42ca632f55SGrant Likely 43ca632f55SGrant Likely #define SPI_CTRL2 0x01 44ca632f55SGrant Likely #define SPI_BRR 0x04 45ca632f55SGrant Likely 46ca632f55SGrant Likely #define SPI_STATUS 0x05 47ca632f55SGrant Likely #define SPI_STATUS_SPIF (1 << 7) 48ca632f55SGrant Likely #define SPI_STATUS_WCOL (1 << 6) 49ca632f55SGrant Likely #define SPI_STATUS_MODF (1 << 4) 50ca632f55SGrant Likely 51ca632f55SGrant Likely #define SPI_DATA 0x09 52ca632f55SGrant Likely #define SPI_PORTDATA 0x0d 53ca632f55SGrant Likely #define SPI_DATADIR 0x10 54ca632f55SGrant Likely 55ca632f55SGrant Likely /* FSM state return values */ 56ca632f55SGrant Likely #define FSM_STOP 0 /* Nothing more for the state machine to */ 57ca632f55SGrant Likely /* do. If something interesting happens */ 58ca632f55SGrant Likely /* then an IRQ will be received */ 59ca632f55SGrant Likely #define FSM_POLL 1 /* need to poll for completion, an IRQ is */ 60ca632f55SGrant Likely /* not expected */ 61ca632f55SGrant Likely #define FSM_CONTINUE 2 /* Keep iterating the state machine */ 62ca632f55SGrant Likely 63ca632f55SGrant Likely /* Driver internal data */ 64ca632f55SGrant Likely struct mpc52xx_spi { 65ca632f55SGrant Likely struct spi_master *master; 66ca632f55SGrant Likely void __iomem *regs; 67ca632f55SGrant Likely int irq0; /* MODF irq */ 68ca632f55SGrant Likely int irq1; /* SPIF irq */ 69ca632f55SGrant Likely unsigned int ipb_freq; 70ca632f55SGrant Likely 71ca632f55SGrant Likely /* Statistics; not used now, but will be reintroduced for debugfs */ 72ca632f55SGrant Likely int msg_count; 73ca632f55SGrant Likely int wcol_count; 74ca632f55SGrant Likely int wcol_ticks; 75ca632f55SGrant Likely u32 wcol_tx_timestamp; 76ca632f55SGrant Likely int modf_count; 77ca632f55SGrant Likely int byte_count; 78ca632f55SGrant Likely 79ca632f55SGrant Likely struct list_head queue; /* queue of pending messages */ 80ca632f55SGrant Likely spinlock_t lock; 81ca632f55SGrant Likely struct work_struct work; 82ca632f55SGrant Likely 83ca632f55SGrant Likely /* Details of current transfer (length, and buffer pointers) */ 84ca632f55SGrant Likely struct spi_message *message; /* current message */ 85ca632f55SGrant Likely struct spi_transfer *transfer; /* current transfer */ 86ca632f55SGrant Likely int (*state)(int irq, struct mpc52xx_spi *ms, u8 status, u8 data); 87ca632f55SGrant Likely int len; 88ca632f55SGrant Likely int timestamp; 89ca632f55SGrant Likely u8 *rx_buf; 90ca632f55SGrant Likely const u8 *tx_buf; 91ca632f55SGrant Likely int cs_change; 92ca632f55SGrant Likely int gpio_cs_count; 932f3a896bSDmitry Torokhov struct gpio_desc **gpio_cs; 94ca632f55SGrant Likely }; 95ca632f55SGrant Likely 96ca632f55SGrant Likely /* 97ca632f55SGrant Likely * CS control function 98ca632f55SGrant Likely */ 99ca632f55SGrant Likely static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value) 100ca632f55SGrant Likely { 101ca632f55SGrant Likely int cs; 102ca632f55SGrant Likely 103ca632f55SGrant Likely if (ms->gpio_cs_count > 0) { 104ca632f55SGrant Likely cs = ms->message->spi->chip_select; 1052f3a896bSDmitry Torokhov gpiod_set_value(ms->gpio_cs[cs], value); 1062f3a896bSDmitry Torokhov } else { 107ca632f55SGrant Likely out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08); 108ca632f55SGrant Likely } 1092f3a896bSDmitry Torokhov } 110ca632f55SGrant Likely 111ca632f55SGrant Likely /* 112ca632f55SGrant Likely * Start a new transfer. This is called both by the idle state 113ca632f55SGrant Likely * for the first transfer in a message, and by the wait state when the 114ca632f55SGrant Likely * previous transfer in a message is complete. 115ca632f55SGrant Likely */ 116ca632f55SGrant Likely static void mpc52xx_spi_start_transfer(struct mpc52xx_spi *ms) 117ca632f55SGrant Likely { 118ca632f55SGrant Likely ms->rx_buf = ms->transfer->rx_buf; 119ca632f55SGrant Likely ms->tx_buf = ms->transfer->tx_buf; 120ca632f55SGrant Likely ms->len = ms->transfer->len; 121ca632f55SGrant Likely 122ca632f55SGrant Likely /* Activate the chip select */ 123ca632f55SGrant Likely if (ms->cs_change) 124ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 1); 125ca632f55SGrant Likely ms->cs_change = ms->transfer->cs_change; 126ca632f55SGrant Likely 127ca632f55SGrant Likely /* Write out the first byte */ 128e1065611SChristophe Leroy ms->wcol_tx_timestamp = mftb(); 129ca632f55SGrant Likely if (ms->tx_buf) 130ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, *ms->tx_buf++); 131ca632f55SGrant Likely else 132ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, 0); 133ca632f55SGrant Likely } 134ca632f55SGrant Likely 135ca632f55SGrant Likely /* Forward declaration of state handlers */ 136ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, 137ca632f55SGrant Likely u8 status, u8 data); 138ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, 139ca632f55SGrant Likely u8 status, u8 data); 140ca632f55SGrant Likely 141ca632f55SGrant Likely /* 142ca632f55SGrant Likely * IDLE state 143ca632f55SGrant Likely * 144ca632f55SGrant Likely * No transfers are in progress; if another transfer is pending then retrieve 145ca632f55SGrant Likely * it and kick it off. Otherwise, stop processing the state machine 146ca632f55SGrant Likely */ 147ca632f55SGrant Likely static int 148ca632f55SGrant Likely mpc52xx_spi_fsmstate_idle(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) 149ca632f55SGrant Likely { 150ca632f55SGrant Likely struct spi_device *spi; 151ca632f55SGrant Likely int spr, sppr; 152ca632f55SGrant Likely u8 ctrl1; 153ca632f55SGrant Likely 154b25fe93fSChristophe Leroy if (status && irq) 155ca632f55SGrant Likely dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", 156ca632f55SGrant Likely status); 157ca632f55SGrant Likely 158ca632f55SGrant Likely /* Check if there is another transfer waiting. */ 159ca632f55SGrant Likely if (list_empty(&ms->queue)) 160ca632f55SGrant Likely return FSM_STOP; 161ca632f55SGrant Likely 162ca632f55SGrant Likely /* get the head of the queue */ 163ca632f55SGrant Likely ms->message = list_first_entry(&ms->queue, struct spi_message, queue); 164ca632f55SGrant Likely list_del_init(&ms->message->queue); 165ca632f55SGrant Likely 166ca632f55SGrant Likely /* Setup the controller parameters */ 167ca632f55SGrant Likely ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; 168ca632f55SGrant Likely spi = ms->message->spi; 169ca632f55SGrant Likely if (spi->mode & SPI_CPHA) 170ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_CPHA; 171ca632f55SGrant Likely if (spi->mode & SPI_CPOL) 172ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_CPOL; 173ca632f55SGrant Likely if (spi->mode & SPI_LSB_FIRST) 174ca632f55SGrant Likely ctrl1 |= SPI_CTRL1_LSBFE; 175ca632f55SGrant Likely out_8(ms->regs + SPI_CTRL1, ctrl1); 176ca632f55SGrant Likely 177ca632f55SGrant Likely /* Setup the controller speed */ 178ca632f55SGrant Likely /* minimum divider is '2'. Also, add '1' to force rounding the 179ca632f55SGrant Likely * divider up. */ 180ca632f55SGrant Likely sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1; 181ca632f55SGrant Likely spr = 0; 182ca632f55SGrant Likely if (sppr < 1) 183ca632f55SGrant Likely sppr = 1; 184ca632f55SGrant Likely while (((sppr - 1) & ~0x7) != 0) { 185ca632f55SGrant Likely sppr = (sppr + 1) >> 1; /* add '1' to force rounding up */ 186ca632f55SGrant Likely spr++; 187ca632f55SGrant Likely } 188ca632f55SGrant Likely sppr--; /* sppr quantity in register is offset by 1 */ 189ca632f55SGrant Likely if (spr > 7) { 190ca632f55SGrant Likely /* Don't overrun limits of SPI baudrate register */ 191ca632f55SGrant Likely spr = 7; 192ca632f55SGrant Likely sppr = 7; 193ca632f55SGrant Likely } 194ca632f55SGrant Likely out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */ 195ca632f55SGrant Likely 196ca632f55SGrant Likely ms->cs_change = 1; 197ca632f55SGrant Likely ms->transfer = container_of(ms->message->transfers.next, 198ca632f55SGrant Likely struct spi_transfer, transfer_list); 199ca632f55SGrant Likely 200ca632f55SGrant Likely mpc52xx_spi_start_transfer(ms); 201ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_transfer; 202ca632f55SGrant Likely 203ca632f55SGrant Likely return FSM_CONTINUE; 204ca632f55SGrant Likely } 205ca632f55SGrant Likely 206ca632f55SGrant Likely /* 207ca632f55SGrant Likely * TRANSFER state 208ca632f55SGrant Likely * 209ca632f55SGrant Likely * In the middle of a transfer. If the SPI core has completed processing 210ca632f55SGrant Likely * a byte, then read out the received data and write out the next byte 211ca632f55SGrant Likely * (unless this transfer is finished; in which case go on to the wait 212ca632f55SGrant Likely * state) 213ca632f55SGrant Likely */ 214ca632f55SGrant Likely static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms, 215ca632f55SGrant Likely u8 status, u8 data) 216ca632f55SGrant Likely { 217ca632f55SGrant Likely if (!status) 218ca632f55SGrant Likely return ms->irq0 ? FSM_STOP : FSM_POLL; 219ca632f55SGrant Likely 220ca632f55SGrant Likely if (status & SPI_STATUS_WCOL) { 221ca632f55SGrant Likely /* The SPI controller is stoopid. At slower speeds, it may 222ca632f55SGrant Likely * raise the SPIF flag before the state machine is actually 223ca632f55SGrant Likely * finished, which causes a collision (internal to the state 224ca632f55SGrant Likely * machine only). The manual recommends inserting a delay 225ca632f55SGrant Likely * between receiving the interrupt and sending the next byte, 226ca632f55SGrant Likely * but it can also be worked around simply by retrying the 227ca632f55SGrant Likely * transfer which is what we do here. */ 228ca632f55SGrant Likely ms->wcol_count++; 229e1065611SChristophe Leroy ms->wcol_ticks += mftb() - ms->wcol_tx_timestamp; 230e1065611SChristophe Leroy ms->wcol_tx_timestamp = mftb(); 231ca632f55SGrant Likely data = 0; 232ca632f55SGrant Likely if (ms->tx_buf) 233ca632f55SGrant Likely data = *(ms->tx_buf - 1); 234ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, data); /* try again */ 235ca632f55SGrant Likely return FSM_CONTINUE; 236ca632f55SGrant Likely } else if (status & SPI_STATUS_MODF) { 237ca632f55SGrant Likely ms->modf_count++; 238ca632f55SGrant Likely dev_err(&ms->master->dev, "mode fault\n"); 239ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 240ca632f55SGrant Likely ms->message->status = -EIO; 2410a6d3879SAxel Lin if (ms->message->complete) 242ca632f55SGrant Likely ms->message->complete(ms->message->context); 243ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 244ca632f55SGrant Likely return FSM_CONTINUE; 245ca632f55SGrant Likely } 246ca632f55SGrant Likely 247ca632f55SGrant Likely /* Read data out of the spi device */ 248ca632f55SGrant Likely ms->byte_count++; 249ca632f55SGrant Likely if (ms->rx_buf) 250ca632f55SGrant Likely *ms->rx_buf++ = data; 251ca632f55SGrant Likely 252ca632f55SGrant Likely /* Is the transfer complete? */ 253ca632f55SGrant Likely ms->len--; 254ca632f55SGrant Likely if (ms->len == 0) { 255e1065611SChristophe Leroy ms->timestamp = mftb(); 256258ea99fSSergiu Cuciurean if (ms->transfer->delay.unit == SPI_DELAY_UNIT_USECS) 257258ea99fSSergiu Cuciurean ms->timestamp += ms->transfer->delay.value * 258258ea99fSSergiu Cuciurean tb_ticks_per_usec; 259ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_wait; 260ca632f55SGrant Likely return FSM_CONTINUE; 261ca632f55SGrant Likely } 262ca632f55SGrant Likely 263ca632f55SGrant Likely /* Write out the next byte */ 264e1065611SChristophe Leroy ms->wcol_tx_timestamp = mftb(); 265ca632f55SGrant Likely if (ms->tx_buf) 266ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, *ms->tx_buf++); 267ca632f55SGrant Likely else 268ca632f55SGrant Likely out_8(ms->regs + SPI_DATA, 0); 269ca632f55SGrant Likely 270ca632f55SGrant Likely return FSM_CONTINUE; 271ca632f55SGrant Likely } 272ca632f55SGrant Likely 273ca632f55SGrant Likely /* 274ca632f55SGrant Likely * WAIT state 275ca632f55SGrant Likely * 276ca632f55SGrant Likely * A transfer has completed; need to wait for the delay period to complete 277ca632f55SGrant Likely * before starting the next transfer 278ca632f55SGrant Likely */ 279ca632f55SGrant Likely static int 280ca632f55SGrant Likely mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data) 281ca632f55SGrant Likely { 282ca632f55SGrant Likely if (status && irq) 283ca632f55SGrant Likely dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", 284ca632f55SGrant Likely status); 285ca632f55SGrant Likely 286e1065611SChristophe Leroy if (((int)mftb()) - ms->timestamp < 0) 287ca632f55SGrant Likely return FSM_POLL; 288ca632f55SGrant Likely 289ca632f55SGrant Likely ms->message->actual_length += ms->transfer->len; 290ca632f55SGrant Likely 291ca632f55SGrant Likely /* Check if there is another transfer in this message. If there 292ca632f55SGrant Likely * aren't then deactivate CS, notify sender, and drop back to idle 293ca632f55SGrant Likely * to start the next message. */ 294ca632f55SGrant Likely if (ms->transfer->transfer_list.next == &ms->message->transfers) { 295ca632f55SGrant Likely ms->msg_count++; 296ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 297ca632f55SGrant Likely ms->message->status = 0; 2980a6d3879SAxel Lin if (ms->message->complete) 299ca632f55SGrant Likely ms->message->complete(ms->message->context); 300ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 301ca632f55SGrant Likely return FSM_CONTINUE; 302ca632f55SGrant Likely } 303ca632f55SGrant Likely 304ca632f55SGrant Likely /* There is another transfer; kick it off */ 305ca632f55SGrant Likely 306ca632f55SGrant Likely if (ms->cs_change) 307ca632f55SGrant Likely mpc52xx_spi_chipsel(ms, 0); 308ca632f55SGrant Likely 309ca632f55SGrant Likely ms->transfer = container_of(ms->transfer->transfer_list.next, 310ca632f55SGrant Likely struct spi_transfer, transfer_list); 311ca632f55SGrant Likely mpc52xx_spi_start_transfer(ms); 312ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_transfer; 313ca632f55SGrant Likely return FSM_CONTINUE; 314ca632f55SGrant Likely } 315ca632f55SGrant Likely 316ca632f55SGrant Likely /** 317ca632f55SGrant Likely * mpc52xx_spi_fsm_process - Finite State Machine iteration function 318ca632f55SGrant Likely * @irq: irq number that triggered the FSM or 0 for polling 319ca632f55SGrant Likely * @ms: pointer to mpc52xx_spi driver data 320ca632f55SGrant Likely */ 321ca632f55SGrant Likely static void mpc52xx_spi_fsm_process(int irq, struct mpc52xx_spi *ms) 322ca632f55SGrant Likely { 323ca632f55SGrant Likely int rc = FSM_CONTINUE; 324ca632f55SGrant Likely u8 status, data; 325ca632f55SGrant Likely 326ca632f55SGrant Likely while (rc == FSM_CONTINUE) { 327ca632f55SGrant Likely /* Interrupt cleared by read of STATUS followed by 328ca632f55SGrant Likely * read of DATA registers */ 329ca632f55SGrant Likely status = in_8(ms->regs + SPI_STATUS); 330ca632f55SGrant Likely data = in_8(ms->regs + SPI_DATA); 331ca632f55SGrant Likely rc = ms->state(irq, ms, status, data); 332ca632f55SGrant Likely } 333ca632f55SGrant Likely 334ca632f55SGrant Likely if (rc == FSM_POLL) 335ca632f55SGrant Likely schedule_work(&ms->work); 336ca632f55SGrant Likely } 337ca632f55SGrant Likely 338ca632f55SGrant Likely /** 339ca632f55SGrant Likely * mpc52xx_spi_irq - IRQ handler 340ca632f55SGrant Likely */ 341ca632f55SGrant Likely static irqreturn_t mpc52xx_spi_irq(int irq, void *_ms) 342ca632f55SGrant Likely { 343ca632f55SGrant Likely struct mpc52xx_spi *ms = _ms; 344ca632f55SGrant Likely spin_lock(&ms->lock); 345ca632f55SGrant Likely mpc52xx_spi_fsm_process(irq, ms); 346ca632f55SGrant Likely spin_unlock(&ms->lock); 347ca632f55SGrant Likely return IRQ_HANDLED; 348ca632f55SGrant Likely } 349ca632f55SGrant Likely 350ca632f55SGrant Likely /** 351ca632f55SGrant Likely * mpc52xx_spi_wq - Workqueue function for polling the state machine 352ca632f55SGrant Likely */ 353ca632f55SGrant Likely static void mpc52xx_spi_wq(struct work_struct *work) 354ca632f55SGrant Likely { 355ca632f55SGrant Likely struct mpc52xx_spi *ms = container_of(work, struct mpc52xx_spi, work); 356ca632f55SGrant Likely unsigned long flags; 357ca632f55SGrant Likely 358ca632f55SGrant Likely spin_lock_irqsave(&ms->lock, flags); 359ca632f55SGrant Likely mpc52xx_spi_fsm_process(0, ms); 360ca632f55SGrant Likely spin_unlock_irqrestore(&ms->lock, flags); 361ca632f55SGrant Likely } 362ca632f55SGrant Likely 363ca632f55SGrant Likely /* 364ca632f55SGrant Likely * spi_master ops 365ca632f55SGrant Likely */ 366ca632f55SGrant Likely 367ca632f55SGrant Likely static int mpc52xx_spi_transfer(struct spi_device *spi, struct spi_message *m) 368ca632f55SGrant Likely { 369ca632f55SGrant Likely struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master); 370ca632f55SGrant Likely unsigned long flags; 371ca632f55SGrant Likely 372ca632f55SGrant Likely m->actual_length = 0; 373ca632f55SGrant Likely m->status = -EINPROGRESS; 374ca632f55SGrant Likely 375ca632f55SGrant Likely spin_lock_irqsave(&ms->lock, flags); 376ca632f55SGrant Likely list_add_tail(&m->queue, &ms->queue); 377ca632f55SGrant Likely spin_unlock_irqrestore(&ms->lock, flags); 378ca632f55SGrant Likely schedule_work(&ms->work); 379ca632f55SGrant Likely 380ca632f55SGrant Likely return 0; 381ca632f55SGrant Likely } 382ca632f55SGrant Likely 383ca632f55SGrant Likely /* 384ca632f55SGrant Likely * OF Platform Bus Binding 385ca632f55SGrant Likely */ 386fd4a319bSGrant Likely static int mpc52xx_spi_probe(struct platform_device *op) 387ca632f55SGrant Likely { 388ca632f55SGrant Likely struct spi_master *master; 389ca632f55SGrant Likely struct mpc52xx_spi *ms; 3902f3a896bSDmitry Torokhov struct gpio_desc *gpio_cs; 391ca632f55SGrant Likely void __iomem *regs; 392ca632f55SGrant Likely u8 ctrl1; 393ca632f55SGrant Likely int rc, i = 0; 394ca632f55SGrant Likely 395ca632f55SGrant Likely /* MMIO registers */ 396ca632f55SGrant Likely dev_dbg(&op->dev, "probing mpc5200 SPI device\n"); 397ca632f55SGrant Likely regs = of_iomap(op->dev.of_node, 0); 398ca632f55SGrant Likely if (!regs) 399ca632f55SGrant Likely return -ENODEV; 400ca632f55SGrant Likely 401ca632f55SGrant Likely /* initialize the device */ 402ca632f55SGrant Likely ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR; 403ca632f55SGrant Likely out_8(regs + SPI_CTRL1, ctrl1); 404ca632f55SGrant Likely out_8(regs + SPI_CTRL2, 0x0); 405ca632f55SGrant Likely out_8(regs + SPI_DATADIR, 0xe); /* Set output pins */ 406ca632f55SGrant Likely out_8(regs + SPI_PORTDATA, 0x8); /* Deassert /SS signal */ 407ca632f55SGrant Likely 408ca632f55SGrant Likely /* Clear the status register and re-read it to check for a MODF 409ca632f55SGrant Likely * failure. This driver cannot currently handle multiple masters 410ca632f55SGrant Likely * on the SPI bus. This fault will also occur if the SPI signals 411ca632f55SGrant Likely * are not connected to any pins (port_config setting) */ 412ca632f55SGrant Likely in_8(regs + SPI_STATUS); 413ca632f55SGrant Likely out_8(regs + SPI_CTRL1, ctrl1); 414ca632f55SGrant Likely 415ca632f55SGrant Likely in_8(regs + SPI_DATA); 416ca632f55SGrant Likely if (in_8(regs + SPI_STATUS) & SPI_STATUS_MODF) { 417ca632f55SGrant Likely dev_err(&op->dev, "mode fault; is port_config correct?\n"); 418ca632f55SGrant Likely rc = -EIO; 419ca632f55SGrant Likely goto err_init; 420ca632f55SGrant Likely } 421ca632f55SGrant Likely 422ca632f55SGrant Likely dev_dbg(&op->dev, "allocating spi_master struct\n"); 423ac7357acSZhiqi Song master = spi_alloc_master(&op->dev, sizeof(*ms)); 424ca632f55SGrant Likely if (!master) { 425ca632f55SGrant Likely rc = -ENOMEM; 426ca632f55SGrant Likely goto err_alloc; 427ca632f55SGrant Likely } 428ca632f55SGrant Likely 429ca632f55SGrant Likely master->transfer = mpc52xx_spi_transfer; 430ca632f55SGrant Likely master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; 4315c5989ccSAxel Lin master->bits_per_word_mask = SPI_BPW_MASK(8); 432ca632f55SGrant Likely master->dev.of_node = op->dev.of_node; 433ca632f55SGrant Likely 43424b5a82cSJingoo Han platform_set_drvdata(op, master); 435ca632f55SGrant Likely 436ca632f55SGrant Likely ms = spi_master_get_devdata(master); 437ca632f55SGrant Likely ms->master = master; 438ca632f55SGrant Likely ms->regs = regs; 439ca632f55SGrant Likely ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0); 440ca632f55SGrant Likely ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1); 441ca632f55SGrant Likely ms->state = mpc52xx_spi_fsmstate_idle; 442de06fba6SAndy Shevchenko ms->ipb_freq = mpc5xxx_get_bus_frequency(&op->dev); 443a0c4b120SAndy Shevchenko ms->gpio_cs_count = gpiod_count(&op->dev, NULL); 444ca632f55SGrant Likely if (ms->gpio_cs_count > 0) { 445ca632f55SGrant Likely master->num_chipselect = ms->gpio_cs_count; 4468b6c8955SMarkus Elfring ms->gpio_cs = kmalloc_array(ms->gpio_cs_count, 4478b6c8955SMarkus Elfring sizeof(*ms->gpio_cs), 448ca632f55SGrant Likely GFP_KERNEL); 449ca632f55SGrant Likely if (!ms->gpio_cs) { 450ca632f55SGrant Likely rc = -ENOMEM; 451866c0f25SGuenter Roeck goto err_alloc_gpio; 452ca632f55SGrant Likely } 453ca632f55SGrant Likely 454ca632f55SGrant Likely for (i = 0; i < ms->gpio_cs_count; i++) { 4552f3a896bSDmitry Torokhov gpio_cs = gpiod_get_index(&op->dev, 4562f3a896bSDmitry Torokhov NULL, i, GPIOD_OUT_LOW); 4572f3a896bSDmitry Torokhov rc = PTR_ERR_OR_ZERO(gpio_cs); 458ca632f55SGrant Likely if (rc) { 459ca632f55SGrant Likely dev_err(&op->dev, 4602f3a896bSDmitry Torokhov "failed to get spi cs gpio #%d: %d\n", 4612f3a896bSDmitry Torokhov i, rc); 462ca632f55SGrant Likely goto err_gpio; 463ca632f55SGrant Likely } 464ca632f55SGrant Likely 465ca632f55SGrant Likely ms->gpio_cs[i] = gpio_cs; 466ca632f55SGrant Likely } 467ca632f55SGrant Likely } 468ca632f55SGrant Likely 469ca632f55SGrant Likely spin_lock_init(&ms->lock); 470ca632f55SGrant Likely INIT_LIST_HEAD(&ms->queue); 471ca632f55SGrant Likely INIT_WORK(&ms->work, mpc52xx_spi_wq); 472ca632f55SGrant Likely 473ca632f55SGrant Likely /* Decide if interrupts can be used */ 474ca632f55SGrant Likely if (ms->irq0 && ms->irq1) { 475ca632f55SGrant Likely rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0, 476ca632f55SGrant Likely "mpc5200-spi-modf", ms); 477ca632f55SGrant Likely rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0, 478ca632f55SGrant Likely "mpc5200-spi-spif", ms); 479ca632f55SGrant Likely if (rc) { 480ca632f55SGrant Likely free_irq(ms->irq0, ms); 481ca632f55SGrant Likely free_irq(ms->irq1, ms); 482ca632f55SGrant Likely ms->irq0 = ms->irq1 = 0; 483ca632f55SGrant Likely } 484ca632f55SGrant Likely } else { 485ca632f55SGrant Likely /* operate in polled mode */ 486ca632f55SGrant Likely ms->irq0 = ms->irq1 = 0; 487ca632f55SGrant Likely } 488ca632f55SGrant Likely 489ca632f55SGrant Likely if (!ms->irq0) 490ca632f55SGrant Likely dev_info(&op->dev, "using polled mode\n"); 491ca632f55SGrant Likely 492ca632f55SGrant Likely dev_dbg(&op->dev, "registering spi_master struct\n"); 493ca632f55SGrant Likely rc = spi_register_master(master); 494ca632f55SGrant Likely if (rc) 495ca632f55SGrant Likely goto err_register; 496ca632f55SGrant Likely 497ca632f55SGrant Likely dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n"); 498ca632f55SGrant Likely 499ca632f55SGrant Likely return rc; 500ca632f55SGrant Likely 501ca632f55SGrant Likely err_register: 502ca632f55SGrant Likely dev_err(&ms->master->dev, "initialization failed\n"); 503ca632f55SGrant Likely err_gpio: 504ca632f55SGrant Likely while (i-- > 0) 5052f3a896bSDmitry Torokhov gpiod_put(ms->gpio_cs[i]); 506ca632f55SGrant Likely 507ca632f55SGrant Likely kfree(ms->gpio_cs); 508866c0f25SGuenter Roeck err_alloc_gpio: 509866c0f25SGuenter Roeck spi_master_put(master); 510ca632f55SGrant Likely err_alloc: 511ca632f55SGrant Likely err_init: 512ca632f55SGrant Likely iounmap(regs); 513ca632f55SGrant Likely return rc; 514ca632f55SGrant Likely } 515ca632f55SGrant Likely 516*3fa689a8SUwe Kleine-König static void mpc52xx_spi_remove(struct platform_device *op) 517ca632f55SGrant Likely { 51824b5a82cSJingoo Han struct spi_master *master = spi_master_get(platform_get_drvdata(op)); 519ca632f55SGrant Likely struct mpc52xx_spi *ms = spi_master_get_devdata(master); 520ca632f55SGrant Likely int i; 521ca632f55SGrant Likely 522ca632f55SGrant Likely free_irq(ms->irq0, ms); 523ca632f55SGrant Likely free_irq(ms->irq1, ms); 524ca632f55SGrant Likely 525ca632f55SGrant Likely for (i = 0; i < ms->gpio_cs_count; i++) 5262f3a896bSDmitry Torokhov gpiod_put(ms->gpio_cs[i]); 527ca632f55SGrant Likely 528ca632f55SGrant Likely kfree(ms->gpio_cs); 529ca632f55SGrant Likely spi_unregister_master(master); 530ca632f55SGrant Likely iounmap(ms->regs); 531f95e1028SGuenter Roeck spi_master_put(master); 532ca632f55SGrant Likely } 533ca632f55SGrant Likely 534fd4a319bSGrant Likely static const struct of_device_id mpc52xx_spi_match[] = { 535ca632f55SGrant Likely { .compatible = "fsl,mpc5200-spi", }, 536ca632f55SGrant Likely {} 537ca632f55SGrant Likely }; 538ca632f55SGrant Likely MODULE_DEVICE_TABLE(of, mpc52xx_spi_match); 539ca632f55SGrant Likely 540ca632f55SGrant Likely static struct platform_driver mpc52xx_spi_of_driver = { 541ca632f55SGrant Likely .driver = { 542ca632f55SGrant Likely .name = "mpc52xx-spi", 543ca632f55SGrant Likely .of_match_table = mpc52xx_spi_match, 544ca632f55SGrant Likely }, 545ca632f55SGrant Likely .probe = mpc52xx_spi_probe, 546*3fa689a8SUwe Kleine-König .remove_new = mpc52xx_spi_remove, 547ca632f55SGrant Likely }; 548940ab889SGrant Likely module_platform_driver(mpc52xx_spi_of_driver); 549