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spi: cadence: Remove _MASK and _OFFSET suffix
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c474b386
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1/*
2 * Cadence SPI controller driver (master mode only)
3 *
4 * Copyright (C) 2008 - 2014 Xilinx, Inc.
5 *
6 * based on Blackfin On-Chip SPI Driver (spi_bfin5xx.c)
7 *
8 * This program is free software; you can redistribute it and/or modify it under
9 * the terms of the GNU General Public License version 2 as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 */
13
14#include <linux/clk.h>
15#include <linux/delay.h>
16#include <linux/interrupt.h>
17#include <linux/io.h>
18#include <linux/module.h>
19#include <linux/of_irq.h>
20#include <linux/of_address.h>
21#include <linux/platform_device.h>
22#include <linux/spi/spi.h>
23
24/* Name of this driver */
25#define CDNS_SPI_NAME "cdns-spi"
26
27/* Register offset definitions */
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28#define CDNS_SPI_CR 0x00 /* Configuration Register, RW */
29#define CDNS_SPI_ISR 0x04 /* Interrupt Status Register, RO */
30#define CDNS_SPI_IER 0x08 /* Interrupt Enable Register, WO */
31#define CDNS_SPI_IDR 0x0c /* Interrupt Disable Register, WO */
32#define CDNS_SPI_IMR 0x10 /* Interrupt Enabled Mask Register, RO */
33#define CDNS_SPI_ER 0x14 /* Enable/Disable Register, RW */
34#define CDNS_SPI_DR 0x18 /* Delay Register, RW */
35#define CDNS_SPI_TXD 0x1C /* Data Transmit Register, WO */
36#define CDNS_SPI_RXD 0x20 /* Data Receive Register, RO */
37#define CDNS_SPI_SICR 0x24 /* Slave Idle Count Register, RW */
38#define CDNS_SPI_THLD 0x28 /* Transmit FIFO Watermark Register,RW */
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39
40/*
41 * SPI Configuration Register bit Masks
42 *
43 * This register contains various control bits that affect the operation
44 * of the SPI controller
45 */
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46#define CDNS_SPI_CR_MANSTRT 0x00010000 /* Manual TX Start */
47#define CDNS_SPI_CR_CPHA 0x00000004 /* Clock Phase Control */
48#define CDNS_SPI_CR_CPOL 0x00000002 /* Clock Polarity Control */
49#define CDNS_SPI_CR_SSCTRL 0x00003C00 /* Slave Select Mask */
50#define CDNS_SPI_CR_PERI_SEL 0x00000200 /* Peripheral Select Decode */
51#define CDNS_SPI_CR_BAUD_DIV 0x00000038 /* Baud Rate Divisor Mask */
52#define CDNS_SPI_CR_MSTREN 0x00000001 /* Master Enable Mask */
53#define CDNS_SPI_CR_MANSTRTEN 0x00008000 /* Manual TX Enable Mask */
54#define CDNS_SPI_CR_SSFORCE 0x00004000 /* Manual SS Enable Mask */
55#define CDNS_SPI_CR_BAUD_DIV_4 0x00000008 /* Default Baud Div Mask */
56#define CDNS_SPI_CR_DEFAULT (CDNS_SPI_CR_MSTREN | \
57 CDNS_SPI_CR_SSCTRL | \
58 CDNS_SPI_CR_SSFORCE | \
59 CDNS_SPI_CR_BAUD_DIV_4)
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60
61/*
62 * SPI Configuration Register - Baud rate and slave select
63 *
64 * These are the values used in the calculation of baud rate divisor and
65 * setting the slave select.
66 */
67
68#define CDNS_SPI_BAUD_DIV_MAX 7 /* Baud rate divisor maximum */
69#define CDNS_SPI_BAUD_DIV_MIN 1 /* Baud rate divisor minimum */
70#define CDNS_SPI_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift in CR */
71#define CDNS_SPI_SS_SHIFT 10 /* Slave Select field shift in CR */
72#define CDNS_SPI_SS0 0x1 /* Slave Select zero */
73
74/*
75 * SPI Interrupt Registers bit Masks
76 *
77 * All the four interrupt registers (Status/Mask/Enable/Disable) have the same
78 * bit definitions.
79 */
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80#define CDNS_SPI_IXR_TXOW 0x00000004 /* SPI TX FIFO Overwater */
81#define CDNS_SPI_IXR_MODF 0x00000002 /* SPI Mode Fault */
82#define CDNS_SPI_IXR_RXNEMTY 0x00000010 /* SPI RX FIFO Not Empty */
83#define CDNS_SPI_IXR_DEFAULT (CDNS_SPI_IXR_TXOW | \
84 CDNS_SPI_IXR_MODF)
85#define CDNS_SPI_IXR_TXFULL 0x00000008 /* SPI TX Full */
86#define CDNS_SPI_IXR_ALL 0x0000007F /* SPI all interrupts */
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87
88/*
89 * SPI Enable Register bit Masks
90 *
91 * This register is used to enable or disable the SPI controller
92 */
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93#define CDNS_SPI_ER_ENABLE 0x00000001 /* SPI Enable Bit Mask */
94#define CDNS_SPI_ER_DISABLE 0x0 /* SPI Disable Bit Mask */
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95
96/* SPI FIFO depth in bytes */
97#define CDNS_SPI_FIFO_DEPTH 128
98
99/* Default number of chip select lines */
100#define CDNS_SPI_DEFAULT_NUM_CS 4
101
102/**
103 * struct cdns_spi - This definition defines spi driver instance
104 * @regs: Virtual address of the SPI controller registers
105 * @ref_clk: Pointer to the peripheral clock
106 * @pclk: Pointer to the APB clock
107 * @speed_hz: Current SPI bus clock speed in Hz
108 * @txbuf: Pointer to the TX buffer
109 * @rxbuf: Pointer to the RX buffer
110 * @tx_bytes: Number of bytes left to transfer
111 * @rx_bytes: Number of bytes requested
112 * @dev_busy: Device busy flag
113 * @is_decoded_cs: Flag for decoder property set or not
114 */
115struct cdns_spi {
116 void __iomem *regs;
117 struct clk *ref_clk;
118 struct clk *pclk;
119 u32 speed_hz;
120 const u8 *txbuf;
121 u8 *rxbuf;
122 int tx_bytes;
123 int rx_bytes;
124 u8 dev_busy;
125 u32 is_decoded_cs;
126};
127
128/* Macros for the SPI controller read/write */
129static inline u32 cdns_spi_read(struct cdns_spi *xspi, u32 offset)
130{
131 return readl_relaxed(xspi->regs + offset);
132}
133
134static inline void cdns_spi_write(struct cdns_spi *xspi, u32 offset, u32 val)
135{
136 writel_relaxed(val, xspi->regs + offset);
137}
138
139/**
140 * cdns_spi_init_hw - Initialize the hardware and configure the SPI controller
141 * @xspi: Pointer to the cdns_spi structure
142 *
143 * On reset the SPI controller is configured to be in master mode, baud rate
144 * divisor is set to 4, threshold value for TX FIFO not full interrupt is set
145 * to 1 and size of the word to be transferred as 8 bit.
146 * This function initializes the SPI controller to disable and clear all the
147 * interrupts, enable manual slave select and manual start, deselect all the
148 * chip select lines, and enable the SPI controller.
149 */
150static void cdns_spi_init_hw(struct cdns_spi *xspi)
151{
24746675 152 u32 ctrl_reg = CDNS_SPI_CR_DEFAULT;
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153
154 if (xspi->is_decoded_cs)
24746675 155 ctrl_reg |= CDNS_SPI_CR_PERI_SEL;
ee0ebe81 156
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157 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE);
158 cdns_spi_write(xspi, CDNS_SPI_IDR, CDNS_SPI_IXR_ALL);
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159
160 /* Clear the RX FIFO */
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161 while (cdns_spi_read(xspi, CDNS_SPI_ISR) & CDNS_SPI_IXR_RXNEMTY)
162 cdns_spi_read(xspi, CDNS_SPI_RXD);
163
164 cdns_spi_write(xspi, CDNS_SPI_ISR, CDNS_SPI_IXR_ALL);
165 cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg);
166 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE);
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167}
168
169/**
170 * cdns_spi_chipselect - Select or deselect the chip select line
171 * @spi: Pointer to the spi_device structure
172 * @is_on: Select(0) or deselect (1) the chip select line
173 */
174static void cdns_spi_chipselect(struct spi_device *spi, bool is_high)
175{
176 struct cdns_spi *xspi = spi_master_get_devdata(spi->master);
177 u32 ctrl_reg;
178
24746675 179 ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR);
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180
181 if (is_high) {
182 /* Deselect the slave */
24746675 183 ctrl_reg |= CDNS_SPI_CR_SSCTRL;
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184 } else {
185 /* Select the slave */
24746675 186 ctrl_reg &= ~CDNS_SPI_CR_SSCTRL;
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187 if (!(xspi->is_decoded_cs))
188 ctrl_reg |= ((~(CDNS_SPI_SS0 << spi->chip_select)) <<
189 CDNS_SPI_SS_SHIFT) &
24746675 190 CDNS_SPI_CR_SSCTRL;
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191 else
192 ctrl_reg |= (spi->chip_select << CDNS_SPI_SS_SHIFT) &
24746675 193 CDNS_SPI_CR_SSCTRL;
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194 }
195
24746675 196 cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg);
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197}
198
199/**
200 * cdns_spi_config_clock_mode - Sets clock polarity and phase
201 * @spi: Pointer to the spi_device structure
202 *
203 * Sets the requested clock polarity and phase.
204 */
205static void cdns_spi_config_clock_mode(struct spi_device *spi)
206{
207 struct cdns_spi *xspi = spi_master_get_devdata(spi->master);
a39e65e9 208 u32 ctrl_reg, new_ctrl_reg;
c474b386 209
24746675 210 new_ctrl_reg = ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR);
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211
212 /* Set the SPI clock phase and clock polarity */
24746675 213 new_ctrl_reg &= ~(CDNS_SPI_CR_CPHA | CDNS_SPI_CR_CPOL);
c474b386 214 if (spi->mode & SPI_CPHA)
24746675 215 new_ctrl_reg |= CDNS_SPI_CR_CPHA;
c474b386 216 if (spi->mode & SPI_CPOL)
24746675 217 new_ctrl_reg |= CDNS_SPI_CR_CPOL;
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218
219 if (new_ctrl_reg != ctrl_reg) {
220 /*
221 * Just writing the CR register does not seem to apply the clock
222 * setting changes. This is problematic when changing the clock
223 * polarity as it will cause the SPI slave to see spurious clock
224 * transitions. To workaround the issue toggle the ER register.
225 */
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226 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE);
227 cdns_spi_write(xspi, CDNS_SPI_CR, new_ctrl_reg);
228 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE);
a39e65e9 229 }
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230}
231
232/**
233 * cdns_spi_config_clock_freq - Sets clock frequency
234 * @spi: Pointer to the spi_device structure
235 * @transfer: Pointer to the spi_transfer structure which provides
236 * information about next transfer setup parameters
237 *
238 * Sets the requested clock frequency.
239 * Note: If the requested frequency is not an exact match with what can be
240 * obtained using the prescalar value the driver sets the clock frequency which
241 * is lower than the requested frequency (maximum lower) for the transfer. If
242 * the requested frequency is higher or lower than that is supported by the SPI
243 * controller the driver will set the highest or lowest frequency supported by
244 * controller.
245 */
246static void cdns_spi_config_clock_freq(struct spi_device *spi,
247 struct spi_transfer *transfer)
248{
249 struct cdns_spi *xspi = spi_master_get_devdata(spi->master);
250 u32 ctrl_reg, baud_rate_val;
251 unsigned long frequency;
252
253 frequency = clk_get_rate(xspi->ref_clk);
254
24746675 255 ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR);
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256
257 /* Set the clock frequency */
258 if (xspi->speed_hz != transfer->speed_hz) {
259 /* first valid value is 1 */
260 baud_rate_val = CDNS_SPI_BAUD_DIV_MIN;
261 while ((baud_rate_val < CDNS_SPI_BAUD_DIV_MAX) &&
262 (frequency / (2 << baud_rate_val)) > transfer->speed_hz)
263 baud_rate_val++;
264
24746675 265 ctrl_reg &= ~CDNS_SPI_CR_BAUD_DIV;
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266 ctrl_reg |= baud_rate_val << CDNS_SPI_BAUD_DIV_SHIFT;
267
268 xspi->speed_hz = frequency / (2 << baud_rate_val);
269 }
24746675 270 cdns_spi_write(xspi, CDNS_SPI_CR, ctrl_reg);
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271}
272
273/**
274 * cdns_spi_setup_transfer - Configure SPI controller for specified transfer
275 * @spi: Pointer to the spi_device structure
276 * @transfer: Pointer to the spi_transfer structure which provides
277 * information about next transfer setup parameters
278 *
279 * Sets the operational mode of SPI controller for the next SPI transfer and
280 * sets the requested clock frequency.
281 *
282 * Return: Always 0
283 */
284static int cdns_spi_setup_transfer(struct spi_device *spi,
285 struct spi_transfer *transfer)
286{
287 struct cdns_spi *xspi = spi_master_get_devdata(spi->master);
288
289 cdns_spi_config_clock_freq(spi, transfer);
290
291 dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u clock speed\n",
292 __func__, spi->mode, spi->bits_per_word,
293 xspi->speed_hz);
294
295 return 0;
296}
297
298/**
299 * cdns_spi_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible
300 * @xspi: Pointer to the cdns_spi structure
301 */
302static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi)
303{
304 unsigned long trans_cnt = 0;
305
306 while ((trans_cnt < CDNS_SPI_FIFO_DEPTH) &&
307 (xspi->tx_bytes > 0)) {
308 if (xspi->txbuf)
24746675 309 cdns_spi_write(xspi, CDNS_SPI_TXD, *xspi->txbuf++);
c474b386 310 else
24746675 311 cdns_spi_write(xspi, CDNS_SPI_TXD, 0);
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312
313 xspi->tx_bytes--;
314 trans_cnt++;
315 }
316}
317
318/**
319 * cdns_spi_irq - Interrupt service routine of the SPI controller
320 * @irq: IRQ number
321 * @dev_id: Pointer to the xspi structure
322 *
323 * This function handles TX empty and Mode Fault interrupts only.
324 * On TX empty interrupt this function reads the received data from RX FIFO and
325 * fills the TX FIFO if there is any data remaining to be transferred.
326 * On Mode Fault interrupt this function indicates that transfer is completed,
327 * the SPI subsystem will identify the error as the remaining bytes to be
328 * transferred is non-zero.
329 *
330 * Return: IRQ_HANDLED when handled; IRQ_NONE otherwise.
331 */
332static irqreturn_t cdns_spi_irq(int irq, void *dev_id)
333{
334 struct spi_master *master = dev_id;
335 struct cdns_spi *xspi = spi_master_get_devdata(master);
336 u32 intr_status, status;
337
338 status = IRQ_NONE;
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339 intr_status = cdns_spi_read(xspi, CDNS_SPI_ISR);
340 cdns_spi_write(xspi, CDNS_SPI_ISR, intr_status);
c474b386 341
24746675 342 if (intr_status & CDNS_SPI_IXR_MODF) {
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343 /* Indicate that transfer is completed, the SPI subsystem will
344 * identify the error as the remaining bytes to be
345 * transferred is non-zero
346 */
24746675 347 cdns_spi_write(xspi, CDNS_SPI_IDR, CDNS_SPI_IXR_DEFAULT);
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348 spi_finalize_current_transfer(master);
349 status = IRQ_HANDLED;
24746675 350 } else if (intr_status & CDNS_SPI_IXR_TXOW) {
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351 unsigned long trans_cnt;
352
353 trans_cnt = xspi->rx_bytes - xspi->tx_bytes;
354
355 /* Read out the data from the RX FIFO */
356 while (trans_cnt) {
357 u8 data;
358
24746675 359 data = cdns_spi_read(xspi, CDNS_SPI_RXD);
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360 if (xspi->rxbuf)
361 *xspi->rxbuf++ = data;
362
363 xspi->rx_bytes--;
364 trans_cnt--;
365 }
366
367 if (xspi->tx_bytes) {
368 /* There is more data to send */
369 cdns_spi_fill_tx_fifo(xspi);
370 } else {
371 /* Transfer is completed */
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372 cdns_spi_write(xspi, CDNS_SPI_IDR,
373 CDNS_SPI_IXR_DEFAULT);
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374 spi_finalize_current_transfer(master);
375 }
376 status = IRQ_HANDLED;
377 }
378
379 return status;
380}
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381static int cdns_prepare_message(struct spi_master *master,
382 struct spi_message *msg)
383{
384 cdns_spi_config_clock_mode(msg->spi);
385 return 0;
386}
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387
388/**
389 * cdns_transfer_one - Initiates the SPI transfer
390 * @master: Pointer to spi_master structure
391 * @spi: Pointer to the spi_device structure
392 * @transfer: Pointer to the spi_transfer structure which provides
393 * information about next transfer parameters
394 *
395 * This function fills the TX FIFO, starts the SPI transfer and
396 * returns a positive transfer count so that core will wait for completion.
397 *
398 * Return: Number of bytes transferred in the last transfer
399 */
400static int cdns_transfer_one(struct spi_master *master,
401 struct spi_device *spi,
402 struct spi_transfer *transfer)
403{
404 struct cdns_spi *xspi = spi_master_get_devdata(master);
405
406 xspi->txbuf = transfer->tx_buf;
407 xspi->rxbuf = transfer->rx_buf;
408 xspi->tx_bytes = transfer->len;
409 xspi->rx_bytes = transfer->len;
410
411 cdns_spi_setup_transfer(spi, transfer);
412
413 cdns_spi_fill_tx_fifo(xspi);
414
24746675 415 cdns_spi_write(xspi, CDNS_SPI_IER, CDNS_SPI_IXR_DEFAULT);
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416 return transfer->len;
417}
418
419/**
420 * cdns_prepare_transfer_hardware - Prepares hardware for transfer.
421 * @master: Pointer to the spi_master structure which provides
422 * information about the controller.
423 *
424 * This function enables SPI master controller.
425 *
426 * Return: 0 always
427 */
428static int cdns_prepare_transfer_hardware(struct spi_master *master)
429{
430 struct cdns_spi *xspi = spi_master_get_devdata(master);
431
24746675 432 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_ENABLE);
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433
434 return 0;
435}
436
437/**
438 * cdns_unprepare_transfer_hardware - Relaxes hardware after transfer
439 * @master: Pointer to the spi_master structure which provides
440 * information about the controller.
441 *
442 * This function disables the SPI master controller.
443 *
444 * Return: 0 always
445 */
446static int cdns_unprepare_transfer_hardware(struct spi_master *master)
447{
448 struct cdns_spi *xspi = spi_master_get_devdata(master);
449
24746675 450 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE);
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451
452 return 0;
453}
454
455/**
456 * cdns_spi_probe - Probe method for the SPI driver
457 * @pdev: Pointer to the platform_device structure
458 *
459 * This function initializes the driver data structures and the hardware.
460 *
461 * Return: 0 on success and error value on error
462 */
463static int cdns_spi_probe(struct platform_device *pdev)
464{
465 int ret = 0, irq;
466 struct spi_master *master;
467 struct cdns_spi *xspi;
468 struct resource *res;
469 u32 num_cs;
470
471 master = spi_alloc_master(&pdev->dev, sizeof(*xspi));
15a1c503 472 if (!master)
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473 return -ENOMEM;
474
475 xspi = spi_master_get_devdata(master);
476 master->dev.of_node = pdev->dev.of_node;
477 platform_set_drvdata(pdev, master);
478
479 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
480 xspi->regs = devm_ioremap_resource(&pdev->dev, res);
481 if (IS_ERR(xspi->regs)) {
482 ret = PTR_ERR(xspi->regs);
483 goto remove_master;
484 }
485
486 xspi->pclk = devm_clk_get(&pdev->dev, "pclk");
487 if (IS_ERR(xspi->pclk)) {
488 dev_err(&pdev->dev, "pclk clock not found.\n");
489 ret = PTR_ERR(xspi->pclk);
490 goto remove_master;
491 }
492
493 xspi->ref_clk = devm_clk_get(&pdev->dev, "ref_clk");
494 if (IS_ERR(xspi->ref_clk)) {
495 dev_err(&pdev->dev, "ref_clk clock not found.\n");
496 ret = PTR_ERR(xspi->ref_clk);
497 goto remove_master;
498 }
499
500 ret = clk_prepare_enable(xspi->pclk);
501 if (ret) {
502 dev_err(&pdev->dev, "Unable to enable APB clock.\n");
503 goto remove_master;
504 }
505
506 ret = clk_prepare_enable(xspi->ref_clk);
507 if (ret) {
508 dev_err(&pdev->dev, "Unable to enable device clock.\n");
509 goto clk_dis_apb;
510 }
511
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512 ret = of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs);
513 if (ret < 0)
514 master->num_chipselect = CDNS_SPI_DEFAULT_NUM_CS;
515 else
516 master->num_chipselect = num_cs;
517
518 ret = of_property_read_u32(pdev->dev.of_node, "is-decoded-cs",
519 &xspi->is_decoded_cs);
520 if (ret < 0)
521 xspi->is_decoded_cs = 0;
522
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523 /* SPI controller initializations */
524 cdns_spi_init_hw(xspi);
525
526 irq = platform_get_irq(pdev, 0);
527 if (irq <= 0) {
528 ret = -ENXIO;
529 dev_err(&pdev->dev, "irq number is invalid\n");
530 goto remove_master;
531 }
532
533 ret = devm_request_irq(&pdev->dev, irq, cdns_spi_irq,
534 0, pdev->name, master);
535 if (ret != 0) {
536 ret = -ENXIO;
537 dev_err(&pdev->dev, "request_irq failed\n");
538 goto remove_master;
539 }
540
c474b386 541 master->prepare_transfer_hardware = cdns_prepare_transfer_hardware;
b48b9488 542 master->prepare_message = cdns_prepare_message;
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543 master->transfer_one = cdns_transfer_one;
544 master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware;
545 master->set_cs = cdns_spi_chipselect;
546 master->mode_bits = SPI_CPOL | SPI_CPHA;
547
548 /* Set to default valid value */
549 master->max_speed_hz = clk_get_rate(xspi->ref_clk) / 4;
550 xspi->speed_hz = master->max_speed_hz;
551
552 master->bits_per_word_mask = SPI_BPW_MASK(8);
553
554 ret = spi_register_master(master);
555 if (ret) {
556 dev_err(&pdev->dev, "spi_register_master failed\n");
557 goto clk_dis_all;
558 }
559
560 return ret;
561
562clk_dis_all:
563 clk_disable_unprepare(xspi->ref_clk);
564clk_dis_apb:
565 clk_disable_unprepare(xspi->pclk);
566remove_master:
567 spi_master_put(master);
568 return ret;
569}
570
571/**
572 * cdns_spi_remove - Remove method for the SPI driver
573 * @pdev: Pointer to the platform_device structure
574 *
575 * This function is called if a device is physically removed from the system or
576 * if the driver module is being unloaded. It frees all resources allocated to
577 * the device.
578 *
579 * Return: 0 on success and error value on error
580 */
581static int cdns_spi_remove(struct platform_device *pdev)
582{
583 struct spi_master *master = platform_get_drvdata(pdev);
584 struct cdns_spi *xspi = spi_master_get_devdata(master);
585
24746675 586 cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE);
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587
588 clk_disable_unprepare(xspi->ref_clk);
589 clk_disable_unprepare(xspi->pclk);
590
591 spi_unregister_master(master);
592
593 return 0;
594}
595
596/**
597 * cdns_spi_suspend - Suspend method for the SPI driver
598 * @dev: Address of the platform_device structure
599 *
600 * This function disables the SPI controller and
601 * changes the driver state to "suspend"
602 *
603 * Return: Always 0
604 */
605static int __maybe_unused cdns_spi_suspend(struct device *dev)
606{
9033a5f9 607 struct platform_device *pdev = to_platform_device(dev);
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608 struct spi_master *master = platform_get_drvdata(pdev);
609 struct cdns_spi *xspi = spi_master_get_devdata(master);
610
611 spi_master_suspend(master);
612
613 clk_disable_unprepare(xspi->ref_clk);
614
615 clk_disable_unprepare(xspi->pclk);
616
617 return 0;
618}
619
620/**
621 * cdns_spi_resume - Resume method for the SPI driver
622 * @dev: Address of the platform_device structure
623 *
624 * This function changes the driver state to "ready"
625 *
626 * Return: 0 on success and error value on error
627 */
628static int __maybe_unused cdns_spi_resume(struct device *dev)
629{
9033a5f9 630 struct platform_device *pdev = to_platform_device(dev);
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631 struct spi_master *master = platform_get_drvdata(pdev);
632 struct cdns_spi *xspi = spi_master_get_devdata(master);
633 int ret = 0;
634
635 ret = clk_prepare_enable(xspi->pclk);
636 if (ret) {
637 dev_err(dev, "Cannot enable APB clock.\n");
638 return ret;
639 }
640
641 ret = clk_prepare_enable(xspi->ref_clk);
642 if (ret) {
643 dev_err(dev, "Cannot enable device clock.\n");
644 clk_disable(xspi->pclk);
645 return ret;
646 }
647 spi_master_resume(master);
648
649 return 0;
650}
651
652static SIMPLE_DEV_PM_OPS(cdns_spi_dev_pm_ops, cdns_spi_suspend,
653 cdns_spi_resume);
654
f7f994a4 655static const struct of_device_id cdns_spi_of_match[] = {
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656 { .compatible = "xlnx,zynq-spi-r1p6" },
657 { .compatible = "cdns,spi-r1p6" },
658 { /* end of table */ }
659};
660MODULE_DEVICE_TABLE(of, cdns_spi_of_match);
661
662/* cdns_spi_driver - This structure defines the SPI subsystem platform driver */
663static struct platform_driver cdns_spi_driver = {
664 .probe = cdns_spi_probe,
665 .remove = cdns_spi_remove,
666 .driver = {
667 .name = CDNS_SPI_NAME,
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668 .of_match_table = cdns_spi_of_match,
669 .pm = &cdns_spi_dev_pm_ops,
670 },
671};
672
673module_platform_driver(cdns_spi_driver);
674
675MODULE_AUTHOR("Xilinx, Inc.");
676MODULE_DESCRIPTION("Cadence SPI driver");
677MODULE_LICENSE("GPL");