Commit | Line | Data |
---|---|---|
ca632f55 | 1 | /* |
30eaed05 WZ |
2 | * Copyright (c) 2009 Nuvoton technology. |
3 | * Wan ZongShun <mcuos.com@gmail.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
ca632f55 | 9 | */ |
30eaed05 | 10 | |
00d2952c | 11 | #include <linux/module.h> |
30eaed05 | 12 | #include <linux/spinlock.h> |
30eaed05 WZ |
13 | #include <linux/interrupt.h> |
14 | #include <linux/delay.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/clk.h> | |
18 | #include <linux/device.h> | |
19 | #include <linux/platform_device.h> | |
20 | #include <linux/gpio.h> | |
21 | #include <linux/io.h> | |
5a0e3ad6 | 22 | #include <linux/slab.h> |
30eaed05 WZ |
23 | |
24 | #include <linux/spi/spi.h> | |
25 | #include <linux/spi/spi_bitbang.h> | |
26 | ||
54ecf4f0 | 27 | #include <linux/platform_data/spi-nuc900.h> |
30eaed05 WZ |
28 | |
29 | /* usi registers offset */ | |
30 | #define USI_CNT 0x00 | |
31 | #define USI_DIV 0x04 | |
32 | #define USI_SSR 0x08 | |
33 | #define USI_RX0 0x10 | |
34 | #define USI_TX0 0x10 | |
35 | ||
36 | /* usi register bit */ | |
37 | #define ENINT (0x01 << 17) | |
38 | #define ENFLG (0x01 << 16) | |
fb534f10 | 39 | #define SLEEP (0x0f << 12) |
30eaed05 | 40 | #define TXNUM (0x03 << 8) |
fb534f10 | 41 | #define TXBITLEN (0x1f << 3) |
30eaed05 WZ |
42 | #define TXNEG (0x01 << 2) |
43 | #define RXNEG (0x01 << 1) | |
44 | #define LSB (0x01 << 10) | |
45 | #define SELECTLEV (0x01 << 2) | |
46 | #define SELECTPOL (0x01 << 31) | |
47 | #define SELECTSLAVE 0x01 | |
48 | #define GOBUSY 0x01 | |
49 | ||
50 | struct nuc900_spi { | |
51 | struct spi_bitbang bitbang; | |
52 | struct completion done; | |
53 | void __iomem *regs; | |
54 | int irq; | |
55 | int len; | |
56 | int count; | |
57 | const unsigned char *tx; | |
58 | unsigned char *rx; | |
59 | struct clk *clk; | |
30eaed05 | 60 | struct spi_master *master; |
30eaed05 WZ |
61 | struct nuc900_spi_info *pdata; |
62 | spinlock_t lock; | |
30eaed05 WZ |
63 | }; |
64 | ||
65 | static inline struct nuc900_spi *to_hw(struct spi_device *sdev) | |
66 | { | |
67 | return spi_master_get_devdata(sdev->master); | |
68 | } | |
69 | ||
70 | static void nuc900_slave_select(struct spi_device *spi, unsigned int ssr) | |
71 | { | |
72 | struct nuc900_spi *hw = to_hw(spi); | |
73 | unsigned int val; | |
74 | unsigned int cs = spi->mode & SPI_CS_HIGH ? 1 : 0; | |
75 | unsigned int cpol = spi->mode & SPI_CPOL ? 1 : 0; | |
76 | unsigned long flags; | |
77 | ||
78 | spin_lock_irqsave(&hw->lock, flags); | |
79 | ||
80 | val = __raw_readl(hw->regs + USI_SSR); | |
81 | ||
82 | if (!cs) | |
83 | val &= ~SELECTLEV; | |
84 | else | |
85 | val |= SELECTLEV; | |
86 | ||
87 | if (!ssr) | |
88 | val &= ~SELECTSLAVE; | |
89 | else | |
90 | val |= SELECTSLAVE; | |
91 | ||
92 | __raw_writel(val, hw->regs + USI_SSR); | |
93 | ||
94 | val = __raw_readl(hw->regs + USI_CNT); | |
95 | ||
96 | if (!cpol) | |
97 | val &= ~SELECTPOL; | |
98 | else | |
99 | val |= SELECTPOL; | |
100 | ||
101 | __raw_writel(val, hw->regs + USI_CNT); | |
102 | ||
103 | spin_unlock_irqrestore(&hw->lock, flags); | |
104 | } | |
105 | ||
106 | static void nuc900_spi_chipsel(struct spi_device *spi, int value) | |
107 | { | |
108 | switch (value) { | |
109 | case BITBANG_CS_INACTIVE: | |
110 | nuc900_slave_select(spi, 0); | |
111 | break; | |
112 | ||
113 | case BITBANG_CS_ACTIVE: | |
114 | nuc900_slave_select(spi, 1); | |
115 | break; | |
116 | } | |
117 | } | |
118 | ||
fb534f10 | 119 | static void nuc900_spi_setup_txnum(struct nuc900_spi *hw, unsigned int txnum) |
30eaed05 WZ |
120 | { |
121 | unsigned int val; | |
122 | unsigned long flags; | |
123 | ||
124 | spin_lock_irqsave(&hw->lock, flags); | |
125 | ||
fb534f10 | 126 | val = __raw_readl(hw->regs + USI_CNT) & ~TXNUM; |
30eaed05 | 127 | |
fb534f10 | 128 | if (txnum) |
30eaed05 WZ |
129 | val |= txnum << 0x08; |
130 | ||
131 | __raw_writel(val, hw->regs + USI_CNT); | |
132 | ||
133 | spin_unlock_irqrestore(&hw->lock, flags); | |
134 | ||
135 | } | |
136 | ||
137 | static void nuc900_spi_setup_txbitlen(struct nuc900_spi *hw, | |
138 | unsigned int txbitlen) | |
139 | { | |
140 | unsigned int val; | |
141 | unsigned long flags; | |
142 | ||
143 | spin_lock_irqsave(&hw->lock, flags); | |
144 | ||
fb534f10 | 145 | val = __raw_readl(hw->regs + USI_CNT) & ~TXBITLEN; |
30eaed05 WZ |
146 | |
147 | val |= (txbitlen << 0x03); | |
148 | ||
149 | __raw_writel(val, hw->regs + USI_CNT); | |
150 | ||
151 | spin_unlock_irqrestore(&hw->lock, flags); | |
152 | } | |
153 | ||
154 | static void nuc900_spi_gobusy(struct nuc900_spi *hw) | |
155 | { | |
156 | unsigned int val; | |
157 | unsigned long flags; | |
158 | ||
159 | spin_lock_irqsave(&hw->lock, flags); | |
160 | ||
161 | val = __raw_readl(hw->regs + USI_CNT); | |
162 | ||
163 | val |= GOBUSY; | |
164 | ||
165 | __raw_writel(val, hw->regs + USI_CNT); | |
166 | ||
167 | spin_unlock_irqrestore(&hw->lock, flags); | |
168 | } | |
169 | ||
30eaed05 WZ |
170 | static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count) |
171 | { | |
172 | return hw->tx ? hw->tx[count] : 0; | |
173 | } | |
174 | ||
175 | static int nuc900_spi_txrx(struct spi_device *spi, struct spi_transfer *t) | |
176 | { | |
177 | struct nuc900_spi *hw = to_hw(spi); | |
178 | ||
179 | hw->tx = t->tx_buf; | |
180 | hw->rx = t->rx_buf; | |
181 | hw->len = t->len; | |
182 | hw->count = 0; | |
183 | ||
184 | __raw_writel(hw_txbyte(hw, 0x0), hw->regs + USI_TX0); | |
185 | ||
186 | nuc900_spi_gobusy(hw); | |
187 | ||
188 | wait_for_completion(&hw->done); | |
189 | ||
190 | return hw->count; | |
191 | } | |
192 | ||
193 | static irqreturn_t nuc900_spi_irq(int irq, void *dev) | |
194 | { | |
195 | struct nuc900_spi *hw = dev; | |
196 | unsigned int status; | |
197 | unsigned int count = hw->count; | |
198 | ||
199 | status = __raw_readl(hw->regs + USI_CNT); | |
200 | __raw_writel(status, hw->regs + USI_CNT); | |
201 | ||
202 | if (status & ENFLG) { | |
203 | hw->count++; | |
204 | ||
205 | if (hw->rx) | |
206 | hw->rx[count] = __raw_readl(hw->regs + USI_RX0); | |
207 | count++; | |
208 | ||
209 | if (count < hw->len) { | |
210 | __raw_writel(hw_txbyte(hw, count), hw->regs + USI_TX0); | |
211 | nuc900_spi_gobusy(hw); | |
212 | } else { | |
213 | complete(&hw->done); | |
214 | } | |
215 | ||
216 | return IRQ_HANDLED; | |
217 | } | |
218 | ||
219 | complete(&hw->done); | |
220 | return IRQ_HANDLED; | |
221 | } | |
222 | ||
223 | static void nuc900_tx_edge(struct nuc900_spi *hw, unsigned int edge) | |
224 | { | |
225 | unsigned int val; | |
226 | unsigned long flags; | |
227 | ||
228 | spin_lock_irqsave(&hw->lock, flags); | |
229 | ||
230 | val = __raw_readl(hw->regs + USI_CNT); | |
231 | ||
232 | if (edge) | |
233 | val |= TXNEG; | |
234 | else | |
235 | val &= ~TXNEG; | |
236 | __raw_writel(val, hw->regs + USI_CNT); | |
237 | ||
238 | spin_unlock_irqrestore(&hw->lock, flags); | |
239 | } | |
240 | ||
241 | static void nuc900_rx_edge(struct nuc900_spi *hw, unsigned int edge) | |
242 | { | |
243 | unsigned int val; | |
244 | unsigned long flags; | |
245 | ||
246 | spin_lock_irqsave(&hw->lock, flags); | |
247 | ||
248 | val = __raw_readl(hw->regs + USI_CNT); | |
249 | ||
250 | if (edge) | |
251 | val |= RXNEG; | |
252 | else | |
253 | val &= ~RXNEG; | |
254 | __raw_writel(val, hw->regs + USI_CNT); | |
255 | ||
256 | spin_unlock_irqrestore(&hw->lock, flags); | |
257 | } | |
258 | ||
259 | static void nuc900_send_first(struct nuc900_spi *hw, unsigned int lsb) | |
260 | { | |
261 | unsigned int val; | |
262 | unsigned long flags; | |
263 | ||
264 | spin_lock_irqsave(&hw->lock, flags); | |
265 | ||
266 | val = __raw_readl(hw->regs + USI_CNT); | |
267 | ||
268 | if (lsb) | |
269 | val |= LSB; | |
270 | else | |
271 | val &= ~LSB; | |
272 | __raw_writel(val, hw->regs + USI_CNT); | |
273 | ||
274 | spin_unlock_irqrestore(&hw->lock, flags); | |
275 | } | |
276 | ||
277 | static void nuc900_set_sleep(struct nuc900_spi *hw, unsigned int sleep) | |
278 | { | |
279 | unsigned int val; | |
280 | unsigned long flags; | |
281 | ||
282 | spin_lock_irqsave(&hw->lock, flags); | |
283 | ||
fb534f10 | 284 | val = __raw_readl(hw->regs + USI_CNT) & ~SLEEP; |
30eaed05 WZ |
285 | |
286 | if (sleep) | |
287 | val |= (sleep << 12); | |
fb534f10 | 288 | |
30eaed05 WZ |
289 | __raw_writel(val, hw->regs + USI_CNT); |
290 | ||
291 | spin_unlock_irqrestore(&hw->lock, flags); | |
292 | } | |
293 | ||
294 | static void nuc900_enable_int(struct nuc900_spi *hw) | |
295 | { | |
296 | unsigned int val; | |
297 | unsigned long flags; | |
298 | ||
299 | spin_lock_irqsave(&hw->lock, flags); | |
300 | ||
301 | val = __raw_readl(hw->regs + USI_CNT); | |
302 | ||
303 | val |= ENINT; | |
304 | ||
305 | __raw_writel(val, hw->regs + USI_CNT); | |
306 | ||
307 | spin_unlock_irqrestore(&hw->lock, flags); | |
308 | } | |
309 | ||
310 | static void nuc900_set_divider(struct nuc900_spi *hw) | |
311 | { | |
312 | __raw_writel(hw->pdata->divider, hw->regs + USI_DIV); | |
313 | } | |
314 | ||
315 | static void nuc900_init_spi(struct nuc900_spi *hw) | |
316 | { | |
317 | clk_enable(hw->clk); | |
318 | spin_lock_init(&hw->lock); | |
319 | ||
320 | nuc900_tx_edge(hw, hw->pdata->txneg); | |
321 | nuc900_rx_edge(hw, hw->pdata->rxneg); | |
322 | nuc900_send_first(hw, hw->pdata->lsb); | |
323 | nuc900_set_sleep(hw, hw->pdata->sleep); | |
324 | nuc900_spi_setup_txbitlen(hw, hw->pdata->txbitlen); | |
325 | nuc900_spi_setup_txnum(hw, hw->pdata->txnum); | |
326 | nuc900_set_divider(hw); | |
327 | nuc900_enable_int(hw); | |
328 | } | |
329 | ||
fd4a319b | 330 | static int nuc900_spi_probe(struct platform_device *pdev) |
30eaed05 WZ |
331 | { |
332 | struct nuc900_spi *hw; | |
333 | struct spi_master *master; | |
8120ff8c | 334 | struct resource *res; |
30eaed05 WZ |
335 | int err = 0; |
336 | ||
337 | master = spi_alloc_master(&pdev->dev, sizeof(struct nuc900_spi)); | |
338 | if (master == NULL) { | |
339 | dev_err(&pdev->dev, "No memory for spi_master\n"); | |
7519459d | 340 | return -ENOMEM; |
30eaed05 WZ |
341 | } |
342 | ||
343 | hw = spi_master_get_devdata(master); | |
94c69f76 | 344 | hw->master = master; |
8074cf06 | 345 | hw->pdata = dev_get_platdata(&pdev->dev); |
30eaed05 WZ |
346 | |
347 | if (hw->pdata == NULL) { | |
348 | dev_err(&pdev->dev, "No platform data supplied\n"); | |
349 | err = -ENOENT; | |
350 | goto err_pdata; | |
351 | } | |
352 | ||
353 | platform_set_drvdata(pdev, hw); | |
354 | init_completion(&hw->done); | |
355 | ||
044d0bb6 | 356 | master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; |
f7db1588 AL |
357 | if (hw->pdata->lsb) |
358 | master->mode_bits |= SPI_LSB_FIRST; | |
30eaed05 WZ |
359 | master->num_chipselect = hw->pdata->num_cs; |
360 | master->bus_num = hw->pdata->bus_num; | |
361 | hw->bitbang.master = hw->master; | |
30eaed05 WZ |
362 | hw->bitbang.chipselect = nuc900_spi_chipsel; |
363 | hw->bitbang.txrx_bufs = nuc900_spi_txrx; | |
30eaed05 | 364 | |
8120ff8c AL |
365 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
366 | hw->regs = devm_ioremap_resource(&pdev->dev, res); | |
7519459d JH |
367 | if (IS_ERR(hw->regs)) { |
368 | err = PTR_ERR(hw->regs); | |
30eaed05 WZ |
369 | goto err_pdata; |
370 | } | |
371 | ||
30eaed05 WZ |
372 | hw->irq = platform_get_irq(pdev, 0); |
373 | if (hw->irq < 0) { | |
374 | dev_err(&pdev->dev, "No IRQ specified\n"); | |
375 | err = -ENOENT; | |
7519459d | 376 | goto err_pdata; |
30eaed05 WZ |
377 | } |
378 | ||
7519459d JH |
379 | err = devm_request_irq(&pdev->dev, hw->irq, nuc900_spi_irq, 0, |
380 | pdev->name, hw); | |
30eaed05 WZ |
381 | if (err) { |
382 | dev_err(&pdev->dev, "Cannot claim IRQ\n"); | |
7519459d | 383 | goto err_pdata; |
30eaed05 WZ |
384 | } |
385 | ||
7519459d | 386 | hw->clk = devm_clk_get(&pdev->dev, "spi"); |
30eaed05 WZ |
387 | if (IS_ERR(hw->clk)) { |
388 | dev_err(&pdev->dev, "No clock for device\n"); | |
389 | err = PTR_ERR(hw->clk); | |
7519459d | 390 | goto err_pdata; |
30eaed05 WZ |
391 | } |
392 | ||
97371fa9 | 393 | mfp_set_groupg(&pdev->dev, NULL); |
30eaed05 WZ |
394 | nuc900_init_spi(hw); |
395 | ||
396 | err = spi_bitbang_start(&hw->bitbang); | |
397 | if (err) { | |
398 | dev_err(&pdev->dev, "Failed to register SPI master\n"); | |
399 | goto err_register; | |
400 | } | |
401 | ||
402 | return 0; | |
403 | ||
404 | err_register: | |
405 | clk_disable(hw->clk); | |
30eaed05 | 406 | err_pdata: |
bc3f67a3 | 407 | spi_master_put(hw->master); |
30eaed05 WZ |
408 | return err; |
409 | } | |
410 | ||
fd4a319b | 411 | static int nuc900_spi_remove(struct platform_device *dev) |
30eaed05 WZ |
412 | { |
413 | struct nuc900_spi *hw = platform_get_drvdata(dev); | |
414 | ||
708a7e43 | 415 | spi_bitbang_stop(&hw->bitbang); |
30eaed05 | 416 | clk_disable(hw->clk); |
30eaed05 WZ |
417 | spi_master_put(hw->master); |
418 | return 0; | |
419 | } | |
420 | ||
421 | static struct platform_driver nuc900_spi_driver = { | |
422 | .probe = nuc900_spi_probe, | |
fd4a319b | 423 | .remove = nuc900_spi_remove, |
30eaed05 WZ |
424 | .driver = { |
425 | .name = "nuc900-spi", | |
30eaed05 WZ |
426 | }, |
427 | }; | |
940ab889 | 428 | module_platform_driver(nuc900_spi_driver); |
30eaed05 WZ |
429 | |
430 | MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>"); | |
431 | MODULE_DESCRIPTION("nuc900 spi driver!"); | |
432 | MODULE_LICENSE("GPL"); | |
433 | MODULE_ALIAS("platform:nuc900-spi"); |