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1/*
2 * Sequencer Serial Port (SSP) based SPI master driver
3 *
4 * Copyright (C) 2010 Texas Instruments Inc
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/err.h>
23#include <linux/completion.h>
24#include <linux/delay.h>
25#include <linux/platform_device.h>
26#include <linux/spi/spi.h>
27#include <linux/mfd/ti_ssp.h>
28
29#define MODE_BITS (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH)
30
31struct ti_ssp_spi {
32 struct spi_master *master;
33 struct device *dev;
34 spinlock_t lock;
35 struct list_head msg_queue;
36 struct completion complete;
37 bool shutdown;
38 struct workqueue_struct *workqueue;
39 struct work_struct work;
40 u8 mode, bpw;
41 int cs_active;
42 u32 pc_en, pc_dis, pc_wr, pc_rd;
43 void (*select)(int cs);
44};
45
46static u32 ti_ssp_spi_rx(struct ti_ssp_spi *hw)
47{
48 u32 ret;
49
50 ti_ssp_run(hw->dev, hw->pc_rd, 0, &ret);
51 return ret;
52}
53
54static void ti_ssp_spi_tx(struct ti_ssp_spi *hw, u32 data)
55{
56 ti_ssp_run(hw->dev, hw->pc_wr, data << (32 - hw->bpw), NULL);
57}
58
59static int ti_ssp_spi_txrx(struct ti_ssp_spi *hw, struct spi_message *msg,
60 struct spi_transfer *t)
61{
62 int count;
63
64 if (hw->bpw <= 8) {
65 u8 *rx = t->rx_buf;
66 const u8 *tx = t->tx_buf;
67
68 for (count = 0; count < t->len; count += 1) {
69 if (t->tx_buf)
70 ti_ssp_spi_tx(hw, *tx++);
71 if (t->rx_buf)
72 *rx++ = ti_ssp_spi_rx(hw);
73 }
74 } else if (hw->bpw <= 16) {
75 u16 *rx = t->rx_buf;
76 const u16 *tx = t->tx_buf;
77
78 for (count = 0; count < t->len; count += 2) {
79 if (t->tx_buf)
80 ti_ssp_spi_tx(hw, *tx++);
81 if (t->rx_buf)
82 *rx++ = ti_ssp_spi_rx(hw);
83 }
84 } else {
85 u32 *rx = t->rx_buf;
86 const u32 *tx = t->tx_buf;
87
88 for (count = 0; count < t->len; count += 4) {
89 if (t->tx_buf)
90 ti_ssp_spi_tx(hw, *tx++);
91 if (t->rx_buf)
92 *rx++ = ti_ssp_spi_rx(hw);
93 }
94 }
95
96 msg->actual_length += count; /* bytes transferred */
97
98 dev_dbg(&msg->spi->dev, "xfer %s%s, %d bytes, %d bpw, count %d%s\n",
99 t->tx_buf ? "tx" : "", t->rx_buf ? "rx" : "", t->len,
100 hw->bpw, count, (count < t->len) ? " (under)" : "");
101
102 return (count < t->len) ? -EIO : 0; /* left over data */
103}
104
105static void ti_ssp_spi_chip_select(struct ti_ssp_spi *hw, int cs_active)
106{
107 cs_active = !!cs_active;
108 if (cs_active == hw->cs_active)
109 return;
110 ti_ssp_run(hw->dev, cs_active ? hw->pc_en : hw->pc_dis, 0, NULL);
111 hw->cs_active = cs_active;
112}
113
114#define __SHIFT_OUT(bits) (SSP_OPCODE_SHIFT | SSP_OUT_MODE | \
115 cs_en | clk | SSP_COUNT((bits) * 2 - 1))
116#define __SHIFT_IN(bits) (SSP_OPCODE_SHIFT | SSP_IN_MODE | \
117 cs_en | clk | SSP_COUNT((bits) * 2 - 1))
118
119static int ti_ssp_spi_setup_transfer(struct ti_ssp_spi *hw, u8 bpw, u8 mode)
120{
121 int error, idx = 0;
122 u32 seqram[16];
123 u32 cs_en, cs_dis, clk;
124 u32 topbits, botbits;
125
126 mode &= MODE_BITS;
127 if (mode == hw->mode && bpw == hw->bpw)
128 return 0;
129
130 cs_en = (mode & SPI_CS_HIGH) ? SSP_CS_HIGH : SSP_CS_LOW;
131 cs_dis = (mode & SPI_CS_HIGH) ? SSP_CS_LOW : SSP_CS_HIGH;
132 clk = (mode & SPI_CPOL) ? SSP_CLK_HIGH : SSP_CLK_LOW;
133
134 /* Construct instructions */
135
136 /* Disable Chip Select */
137 hw->pc_dis = idx;
138 seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_dis | clk;
139 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_dis | clk;
140
141 /* Enable Chip Select */
142 hw->pc_en = idx;
143 seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_en | clk;
144 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
145
146 /* Reads and writes need to be split for bpw > 16 */
147 topbits = (bpw > 16) ? 16 : bpw;
148 botbits = bpw - topbits;
149
150 /* Write */
151 hw->pc_wr = idx;
152 seqram[idx++] = __SHIFT_OUT(topbits) | SSP_ADDR_REG;
153 if (botbits)
154 seqram[idx++] = __SHIFT_OUT(botbits) | SSP_DATA_REG;
155 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
156
157 /* Read */
158 hw->pc_rd = idx;
159 if (botbits)
160 seqram[idx++] = __SHIFT_IN(botbits) | SSP_ADDR_REG;
161 seqram[idx++] = __SHIFT_IN(topbits) | SSP_DATA_REG;
162 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
163
164 error = ti_ssp_load(hw->dev, 0, seqram, idx);
165 if (error < 0)
166 return error;
167
168 error = ti_ssp_set_mode(hw->dev, ((mode & SPI_CPHA) ?
169 0 : SSP_EARLY_DIN));
170 if (error < 0)
171 return error;
172
173 hw->bpw = bpw;
174 hw->mode = mode;
175
176 return error;
177}
178
179static void ti_ssp_spi_work(struct work_struct *work)
180{
181 struct ti_ssp_spi *hw = container_of(work, struct ti_ssp_spi, work);
182
183 spin_lock(&hw->lock);
184
185 while (!list_empty(&hw->msg_queue)) {
186 struct spi_message *m;
187 struct spi_device *spi;
188 struct spi_transfer *t = NULL;
189 int status = 0;
190
191 m = container_of(hw->msg_queue.next, struct spi_message,
192 queue);
193
194 list_del_init(&m->queue);
195
196 spin_unlock(&hw->lock);
197
198 spi = m->spi;
199
200 if (hw->select)
201 hw->select(spi->chip_select);
202
203 list_for_each_entry(t, &m->transfers, transfer_list) {
204 int bpw = spi->bits_per_word;
205 int xfer_status;
206
207 if (t->bits_per_word)
208 bpw = t->bits_per_word;
209
210 if (ti_ssp_spi_setup_transfer(hw, bpw, spi->mode) < 0)
211 break;
212
213 ti_ssp_spi_chip_select(hw, 1);
214
215 xfer_status = ti_ssp_spi_txrx(hw, m, t);
216 if (xfer_status < 0)
217 status = xfer_status;
218
219 if (t->delay_usecs)
220 udelay(t->delay_usecs);
221
222 if (t->cs_change)
223 ti_ssp_spi_chip_select(hw, 0);
224 }
225
226 ti_ssp_spi_chip_select(hw, 0);
227 m->status = status;
228 m->complete(m->context);
229
230 spin_lock(&hw->lock);
231 }
232
233 if (hw->shutdown)
234 complete(&hw->complete);
235
236 spin_unlock(&hw->lock);
237}
238
239static int ti_ssp_spi_setup(struct spi_device *spi)
240{
241 if (spi->bits_per_word > 32)
242 return -EINVAL;
243
244 return 0;
245}
246
247static int ti_ssp_spi_transfer(struct spi_device *spi, struct spi_message *m)
248{
249 struct ti_ssp_spi *hw;
250 struct spi_transfer *t;
251 int error = 0;
252
253 m->actual_length = 0;
254 m->status = -EINPROGRESS;
255
256 hw = spi_master_get_devdata(spi->master);
257
258 if (list_empty(&m->transfers) || !m->complete)
259 return -EINVAL;
260
261 list_for_each_entry(t, &m->transfers, transfer_list) {
262 if (t->len && !(t->rx_buf || t->tx_buf)) {
263 dev_err(&spi->dev, "invalid xfer, no buffer\n");
264 return -EINVAL;
265 }
266
267 if (t->len && t->rx_buf && t->tx_buf) {
268 dev_err(&spi->dev, "invalid xfer, full duplex\n");
269 return -EINVAL;
270 }
271
272 if (t->bits_per_word > 32) {
273 dev_err(&spi->dev, "invalid xfer width %d\n",
274 t->bits_per_word);
275 return -EINVAL;
276 }
277 }
278
279 spin_lock(&hw->lock);
280 if (hw->shutdown) {
281 error = -ESHUTDOWN;
282 goto error_unlock;
283 }
284 list_add_tail(&m->queue, &hw->msg_queue);
285 queue_work(hw->workqueue, &hw->work);
286error_unlock:
287 spin_unlock(&hw->lock);
288 return error;
289}
290
291static int __devinit ti_ssp_spi_probe(struct platform_device *pdev)
292{
293 const struct ti_ssp_spi_data *pdata;
294 struct ti_ssp_spi *hw;
295 struct spi_master *master;
296 struct device *dev = &pdev->dev;
297 int error = 0;
298
299 pdata = dev->platform_data;
300 if (!pdata) {
301 dev_err(dev, "platform data not found\n");
302 return -EINVAL;
303 }
304
305 master = spi_alloc_master(dev, sizeof(struct ti_ssp_spi));
306 if (!master) {
307 dev_err(dev, "cannot allocate SPI master\n");
308 return -ENOMEM;
309 }
310
311 hw = spi_master_get_devdata(master);
312 platform_set_drvdata(pdev, hw);
313
314 hw->master = master;
315 hw->dev = dev;
316 hw->select = pdata->select;
317
318 spin_lock_init(&hw->lock);
319 init_completion(&hw->complete);
320 INIT_LIST_HEAD(&hw->msg_queue);
321 INIT_WORK(&hw->work, ti_ssp_spi_work);
322
323 hw->workqueue = create_singlethread_workqueue(dev_name(dev));
324 if (!hw->workqueue) {
325 error = -ENOMEM;
326 dev_err(dev, "work queue creation failed\n");
327 goto error_wq;
328 }
329
330 error = ti_ssp_set_iosel(hw->dev, pdata->iosel);
331 if (error < 0) {
332 dev_err(dev, "io setup failed\n");
333 goto error_iosel;
334 }
335
336 master->bus_num = pdev->id;
337 master->num_chipselect = pdata->num_cs;
338 master->mode_bits = MODE_BITS;
339 master->flags = SPI_MASTER_HALF_DUPLEX;
340 master->setup = ti_ssp_spi_setup;
341 master->transfer = ti_ssp_spi_transfer;
342
343 error = spi_register_master(master);
344 if (error) {
345 dev_err(dev, "master registration failed\n");
346 goto error_reg;
347 }
348
349 return 0;
350
351error_reg:
352error_iosel:
353 destroy_workqueue(hw->workqueue);
354error_wq:
355 spi_master_put(master);
356 return error;
357}
358
359static int __devexit ti_ssp_spi_remove(struct platform_device *pdev)
360{
361 struct ti_ssp_spi *hw = platform_get_drvdata(pdev);
362 int error;
363
364 hw->shutdown = 1;
365 while (!list_empty(&hw->msg_queue)) {
366 error = wait_for_completion_interruptible(&hw->complete);
367 if (error < 0) {
368 hw->shutdown = 0;
369 return error;
370 }
371 }
372 destroy_workqueue(hw->workqueue);
373 spi_unregister_master(hw->master);
374
375 return 0;
376}
377
378static struct platform_driver ti_ssp_spi_driver = {
379 .probe = ti_ssp_spi_probe,
380 .remove = __devexit_p(ti_ssp_spi_remove),
381 .driver = {
382 .name = "ti-ssp-spi",
383 .owner = THIS_MODULE,
384 },
385};
386
387static int __init ti_ssp_spi_init(void)
388{
389 return platform_driver_register(&ti_ssp_spi_driver);
390}
391module_init(ti_ssp_spi_init);
392
393static void __exit ti_ssp_spi_exit(void)
394{
395 platform_driver_unregister(&ti_ssp_spi_driver);
396}
397module_exit(ti_ssp_spi_exit);
398
399MODULE_DESCRIPTION("SSP SPI Master");
400MODULE_AUTHOR("Cyril Chemparathy");
401MODULE_LICENSE("GPL");
402MODULE_ALIAS("platform:ti-ssp-spi");
1/*
2 * Sequencer Serial Port (SSP) based SPI master driver
3 *
4 * Copyright (C) 2010 Texas Instruments Inc
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/err.h>
23#include <linux/completion.h>
24#include <linux/delay.h>
25#include <linux/module.h>
26#include <linux/platform_device.h>
27#include <linux/spi/spi.h>
28#include <linux/mfd/ti_ssp.h>
29
30#define MODE_BITS (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH)
31
32struct ti_ssp_spi {
33 struct spi_master *master;
34 struct device *dev;
35 spinlock_t lock;
36 struct list_head msg_queue;
37 struct completion complete;
38 bool shutdown;
39 struct workqueue_struct *workqueue;
40 struct work_struct work;
41 u8 mode, bpw;
42 int cs_active;
43 u32 pc_en, pc_dis, pc_wr, pc_rd;
44 void (*select)(int cs);
45};
46
47static u32 ti_ssp_spi_rx(struct ti_ssp_spi *hw)
48{
49 u32 ret;
50
51 ti_ssp_run(hw->dev, hw->pc_rd, 0, &ret);
52 return ret;
53}
54
55static void ti_ssp_spi_tx(struct ti_ssp_spi *hw, u32 data)
56{
57 ti_ssp_run(hw->dev, hw->pc_wr, data << (32 - hw->bpw), NULL);
58}
59
60static int ti_ssp_spi_txrx(struct ti_ssp_spi *hw, struct spi_message *msg,
61 struct spi_transfer *t)
62{
63 int count;
64
65 if (hw->bpw <= 8) {
66 u8 *rx = t->rx_buf;
67 const u8 *tx = t->tx_buf;
68
69 for (count = 0; count < t->len; count += 1) {
70 if (t->tx_buf)
71 ti_ssp_spi_tx(hw, *tx++);
72 if (t->rx_buf)
73 *rx++ = ti_ssp_spi_rx(hw);
74 }
75 } else if (hw->bpw <= 16) {
76 u16 *rx = t->rx_buf;
77 const u16 *tx = t->tx_buf;
78
79 for (count = 0; count < t->len; count += 2) {
80 if (t->tx_buf)
81 ti_ssp_spi_tx(hw, *tx++);
82 if (t->rx_buf)
83 *rx++ = ti_ssp_spi_rx(hw);
84 }
85 } else {
86 u32 *rx = t->rx_buf;
87 const u32 *tx = t->tx_buf;
88
89 for (count = 0; count < t->len; count += 4) {
90 if (t->tx_buf)
91 ti_ssp_spi_tx(hw, *tx++);
92 if (t->rx_buf)
93 *rx++ = ti_ssp_spi_rx(hw);
94 }
95 }
96
97 msg->actual_length += count; /* bytes transferred */
98
99 dev_dbg(&msg->spi->dev, "xfer %s%s, %d bytes, %d bpw, count %d%s\n",
100 t->tx_buf ? "tx" : "", t->rx_buf ? "rx" : "", t->len,
101 hw->bpw, count, (count < t->len) ? " (under)" : "");
102
103 return (count < t->len) ? -EIO : 0; /* left over data */
104}
105
106static void ti_ssp_spi_chip_select(struct ti_ssp_spi *hw, int cs_active)
107{
108 cs_active = !!cs_active;
109 if (cs_active == hw->cs_active)
110 return;
111 ti_ssp_run(hw->dev, cs_active ? hw->pc_en : hw->pc_dis, 0, NULL);
112 hw->cs_active = cs_active;
113}
114
115#define __SHIFT_OUT(bits) (SSP_OPCODE_SHIFT | SSP_OUT_MODE | \
116 cs_en | clk | SSP_COUNT((bits) * 2 - 1))
117#define __SHIFT_IN(bits) (SSP_OPCODE_SHIFT | SSP_IN_MODE | \
118 cs_en | clk | SSP_COUNT((bits) * 2 - 1))
119
120static int ti_ssp_spi_setup_transfer(struct ti_ssp_spi *hw, u8 bpw, u8 mode)
121{
122 int error, idx = 0;
123 u32 seqram[16];
124 u32 cs_en, cs_dis, clk;
125 u32 topbits, botbits;
126
127 mode &= MODE_BITS;
128 if (mode == hw->mode && bpw == hw->bpw)
129 return 0;
130
131 cs_en = (mode & SPI_CS_HIGH) ? SSP_CS_HIGH : SSP_CS_LOW;
132 cs_dis = (mode & SPI_CS_HIGH) ? SSP_CS_LOW : SSP_CS_HIGH;
133 clk = (mode & SPI_CPOL) ? SSP_CLK_HIGH : SSP_CLK_LOW;
134
135 /* Construct instructions */
136
137 /* Disable Chip Select */
138 hw->pc_dis = idx;
139 seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_dis | clk;
140 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_dis | clk;
141
142 /* Enable Chip Select */
143 hw->pc_en = idx;
144 seqram[idx++] = SSP_OPCODE_DIRECT | SSP_OUT_MODE | cs_en | clk;
145 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
146
147 /* Reads and writes need to be split for bpw > 16 */
148 topbits = (bpw > 16) ? 16 : bpw;
149 botbits = bpw - topbits;
150
151 /* Write */
152 hw->pc_wr = idx;
153 seqram[idx++] = __SHIFT_OUT(topbits) | SSP_ADDR_REG;
154 if (botbits)
155 seqram[idx++] = __SHIFT_OUT(botbits) | SSP_DATA_REG;
156 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
157
158 /* Read */
159 hw->pc_rd = idx;
160 if (botbits)
161 seqram[idx++] = __SHIFT_IN(botbits) | SSP_ADDR_REG;
162 seqram[idx++] = __SHIFT_IN(topbits) | SSP_DATA_REG;
163 seqram[idx++] = SSP_OPCODE_STOP | SSP_OUT_MODE | cs_en | clk;
164
165 error = ti_ssp_load(hw->dev, 0, seqram, idx);
166 if (error < 0)
167 return error;
168
169 error = ti_ssp_set_mode(hw->dev, ((mode & SPI_CPHA) ?
170 0 : SSP_EARLY_DIN));
171 if (error < 0)
172 return error;
173
174 hw->bpw = bpw;
175 hw->mode = mode;
176
177 return error;
178}
179
180static void ti_ssp_spi_work(struct work_struct *work)
181{
182 struct ti_ssp_spi *hw = container_of(work, struct ti_ssp_spi, work);
183
184 spin_lock(&hw->lock);
185
186 while (!list_empty(&hw->msg_queue)) {
187 struct spi_message *m;
188 struct spi_device *spi;
189 struct spi_transfer *t = NULL;
190 int status = 0;
191
192 m = container_of(hw->msg_queue.next, struct spi_message,
193 queue);
194
195 list_del_init(&m->queue);
196
197 spin_unlock(&hw->lock);
198
199 spi = m->spi;
200
201 if (hw->select)
202 hw->select(spi->chip_select);
203
204 list_for_each_entry(t, &m->transfers, transfer_list) {
205 int bpw = spi->bits_per_word;
206 int xfer_status;
207
208 if (t->bits_per_word)
209 bpw = t->bits_per_word;
210
211 if (ti_ssp_spi_setup_transfer(hw, bpw, spi->mode) < 0)
212 break;
213
214 ti_ssp_spi_chip_select(hw, 1);
215
216 xfer_status = ti_ssp_spi_txrx(hw, m, t);
217 if (xfer_status < 0)
218 status = xfer_status;
219
220 if (t->delay_usecs)
221 udelay(t->delay_usecs);
222
223 if (t->cs_change)
224 ti_ssp_spi_chip_select(hw, 0);
225 }
226
227 ti_ssp_spi_chip_select(hw, 0);
228 m->status = status;
229 m->complete(m->context);
230
231 spin_lock(&hw->lock);
232 }
233
234 if (hw->shutdown)
235 complete(&hw->complete);
236
237 spin_unlock(&hw->lock);
238}
239
240static int ti_ssp_spi_setup(struct spi_device *spi)
241{
242 if (spi->bits_per_word > 32)
243 return -EINVAL;
244
245 return 0;
246}
247
248static int ti_ssp_spi_transfer(struct spi_device *spi, struct spi_message *m)
249{
250 struct ti_ssp_spi *hw;
251 struct spi_transfer *t;
252 int error = 0;
253
254 m->actual_length = 0;
255 m->status = -EINPROGRESS;
256
257 hw = spi_master_get_devdata(spi->master);
258
259 if (list_empty(&m->transfers) || !m->complete)
260 return -EINVAL;
261
262 list_for_each_entry(t, &m->transfers, transfer_list) {
263 if (t->len && !(t->rx_buf || t->tx_buf)) {
264 dev_err(&spi->dev, "invalid xfer, no buffer\n");
265 return -EINVAL;
266 }
267
268 if (t->len && t->rx_buf && t->tx_buf) {
269 dev_err(&spi->dev, "invalid xfer, full duplex\n");
270 return -EINVAL;
271 }
272
273 if (t->bits_per_word > 32) {
274 dev_err(&spi->dev, "invalid xfer width %d\n",
275 t->bits_per_word);
276 return -EINVAL;
277 }
278 }
279
280 spin_lock(&hw->lock);
281 if (hw->shutdown) {
282 error = -ESHUTDOWN;
283 goto error_unlock;
284 }
285 list_add_tail(&m->queue, &hw->msg_queue);
286 queue_work(hw->workqueue, &hw->work);
287error_unlock:
288 spin_unlock(&hw->lock);
289 return error;
290}
291
292static int __devinit ti_ssp_spi_probe(struct platform_device *pdev)
293{
294 const struct ti_ssp_spi_data *pdata;
295 struct ti_ssp_spi *hw;
296 struct spi_master *master;
297 struct device *dev = &pdev->dev;
298 int error = 0;
299
300 pdata = dev->platform_data;
301 if (!pdata) {
302 dev_err(dev, "platform data not found\n");
303 return -EINVAL;
304 }
305
306 master = spi_alloc_master(dev, sizeof(struct ti_ssp_spi));
307 if (!master) {
308 dev_err(dev, "cannot allocate SPI master\n");
309 return -ENOMEM;
310 }
311
312 hw = spi_master_get_devdata(master);
313 platform_set_drvdata(pdev, hw);
314
315 hw->master = master;
316 hw->dev = dev;
317 hw->select = pdata->select;
318
319 spin_lock_init(&hw->lock);
320 init_completion(&hw->complete);
321 INIT_LIST_HEAD(&hw->msg_queue);
322 INIT_WORK(&hw->work, ti_ssp_spi_work);
323
324 hw->workqueue = create_singlethread_workqueue(dev_name(dev));
325 if (!hw->workqueue) {
326 error = -ENOMEM;
327 dev_err(dev, "work queue creation failed\n");
328 goto error_wq;
329 }
330
331 error = ti_ssp_set_iosel(hw->dev, pdata->iosel);
332 if (error < 0) {
333 dev_err(dev, "io setup failed\n");
334 goto error_iosel;
335 }
336
337 master->bus_num = pdev->id;
338 master->num_chipselect = pdata->num_cs;
339 master->mode_bits = MODE_BITS;
340 master->flags = SPI_MASTER_HALF_DUPLEX;
341 master->setup = ti_ssp_spi_setup;
342 master->transfer = ti_ssp_spi_transfer;
343
344 error = spi_register_master(master);
345 if (error) {
346 dev_err(dev, "master registration failed\n");
347 goto error_reg;
348 }
349
350 return 0;
351
352error_reg:
353error_iosel:
354 destroy_workqueue(hw->workqueue);
355error_wq:
356 spi_master_put(master);
357 return error;
358}
359
360static int __devexit ti_ssp_spi_remove(struct platform_device *pdev)
361{
362 struct ti_ssp_spi *hw = platform_get_drvdata(pdev);
363 int error;
364
365 hw->shutdown = 1;
366 while (!list_empty(&hw->msg_queue)) {
367 error = wait_for_completion_interruptible(&hw->complete);
368 if (error < 0) {
369 hw->shutdown = 0;
370 return error;
371 }
372 }
373 destroy_workqueue(hw->workqueue);
374 spi_unregister_master(hw->master);
375
376 return 0;
377}
378
379static struct platform_driver ti_ssp_spi_driver = {
380 .probe = ti_ssp_spi_probe,
381 .remove = __devexit_p(ti_ssp_spi_remove),
382 .driver = {
383 .name = "ti-ssp-spi",
384 .owner = THIS_MODULE,
385 },
386};
387module_platform_driver(ti_ssp_spi_driver);
388
389MODULE_DESCRIPTION("SSP SPI Master");
390MODULE_AUTHOR("Cyril Chemparathy");
391MODULE_LICENSE("GPL");
392MODULE_ALIAS("platform:ti-ssp-spi");