2 * Mac80211 SPI driver for ST-Ericsson CW1200 device
4 * Copyright (c) 2011, Sagrad Inc.
5 * Author: Solomon Peachy <speachy@sagrad.com>
7 * Based on cw1200_sdio.c
8 * Copyright (c) 2010, ST-Ericsson
9 * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/module.h>
17 #include <linux/gpio.h>
18 #include <linux/delay.h>
19 #include <linux/spinlock.h>
20 #include <linux/interrupt.h>
21 #include <net/mac80211.h>
23 #include <linux/spi/spi.h>
24 #include <linux/device.h>
28 #include <linux/platform_data/net-cw1200.h>
31 MODULE_AUTHOR("Solomon Peachy <speachy@sagrad.com>");
32 MODULE_DESCRIPTION("mac80211 ST-Ericsson CW1200 SPI driver");
33 MODULE_LICENSE("GPL");
34 MODULE_ALIAS("spi:cw1200_wlan_spi");
36 /* #define SPI_DEBUG */
39 struct spi_device *func;
40 struct cw1200_common *core;
41 const struct cw1200_platform_data_spi *pdata;
42 spinlock_t lock; /* Serialize all bus operations */
48 #define SDIO_TO_SPI_ADDR(addr) ((addr & 0x1f)>>2)
49 #define SET_WRITE 0x7FFF /* usage: and operation */
50 #define SET_READ 0x8000 /* usage: or operation */
52 /* Notes on byte ordering:
56 Hardware expects 32-bit data to be written as 16-bit BE words:
61 static int cw1200_spi_memcpy_fromio(struct hwbus_priv *self,
69 struct spi_transfer t_addr = {
71 .len = sizeof(regaddr),
73 struct spi_transfer t_msg = {
78 regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
80 regaddr |= (count>>1);
83 pr_info("READ : %04d from 0x%02x (%04x)\n", count, addr, regaddr);
87 regaddr = cpu_to_le16(regaddr);
89 /* We have to byteswap if the SPI bus is limited to 8b operation
90 or we are running on a Big Endian system
92 #if defined(__LITTLE_ENDIAN)
93 if (self->func->bits_per_word == 8)
95 regaddr = swab16(regaddr);
98 spi_message_add_tail(&t_addr, &m);
99 spi_message_add_tail(&t_msg, &m);
100 ret = spi_sync(self->func, &m);
104 for (i = 0; i < t_addr.len; i++)
105 printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
107 for (i = 0; i < t_msg.len; i++)
108 printk("%02x ", ((u8 *)t_msg.rx_buf)[i]);
112 /* We have to byteswap if the SPI bus is limited to 8b operation
113 or we are running on a Big Endian system
115 #if defined(__LITTLE_ENDIAN)
116 if (self->func->bits_per_word == 8)
119 uint16_t *buf = (uint16_t *)dst;
120 for (i = 0; i < ((count + 1) >> 1); i++)
121 buf[i] = swab16(buf[i]);
127 static int cw1200_spi_memcpy_toio(struct hwbus_priv *self,
129 const void *src, int count)
133 struct spi_transfer t_addr = {
135 .len = sizeof(regaddr),
137 struct spi_transfer t_msg = {
141 struct spi_message m;
143 regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
144 regaddr &= SET_WRITE;
145 regaddr |= (count>>1);
148 pr_info("WRITE: %04d to 0x%02x (%04x)\n", count, addr, regaddr);
152 regaddr = cpu_to_le16(regaddr);
154 /* We have to byteswap if the SPI bus is limited to 8b operation
155 or we are running on a Big Endian system
157 #if defined(__LITTLE_ENDIAN)
158 if (self->func->bits_per_word == 8)
161 uint16_t *buf = (uint16_t *)src;
162 regaddr = swab16(regaddr);
163 for (i = 0; i < ((count + 1) >> 1); i++)
164 buf[i] = swab16(buf[i]);
169 for (i = 0; i < t_addr.len; i++)
170 printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
172 for (i = 0; i < t_msg.len; i++)
173 printk("%02x ", ((u8 *)t_msg.tx_buf)[i]);
177 spi_message_init(&m);
178 spi_message_add_tail(&t_addr, &m);
179 spi_message_add_tail(&t_msg, &m);
180 rval = spi_sync(self->func, &m);
183 pr_info("WROTE: %d\n", m.actual_length);
186 #if defined(__LITTLE_ENDIAN)
187 /* We have to byteswap if the SPI bus is limited to 8b operation */
188 if (self->func->bits_per_word == 8)
191 uint16_t *buf = (uint16_t *)src;
192 for (i = 0; i < ((count + 1) >> 1); i++)
193 buf[i] = swab16(buf[i]);
198 static void cw1200_spi_lock(struct hwbus_priv *self)
202 DECLARE_WAITQUEUE(wait, current);
206 add_wait_queue(&self->wq, &wait);
207 spin_lock_irqsave(&self->lock, flags);
209 set_current_state(TASK_UNINTERRUPTIBLE);
212 spin_unlock_irqrestore(&self->lock, flags);
214 spin_lock_irqsave(&self->lock, flags);
216 set_current_state(TASK_RUNNING);
218 spin_unlock_irqrestore(&self->lock, flags);
219 remove_wait_queue(&self->wq, &wait);
224 static void cw1200_spi_unlock(struct hwbus_priv *self)
228 spin_lock_irqsave(&self->lock, flags);
230 spin_unlock_irqrestore(&self->lock, flags);
236 static irqreturn_t cw1200_spi_irq_handler(int irq, void *dev_id)
238 struct hwbus_priv *self = dev_id;
241 disable_irq_nosync(self->func->irq);
242 self->irq_disabled = 1;
243 cw1200_irq_handler(self->core);
250 static int cw1200_spi_irq_subscribe(struct hwbus_priv *self)
254 pr_debug("SW IRQ subscribe\n");
256 ret = request_any_context_irq(self->func->irq, cw1200_spi_irq_handler,
258 "cw1200_wlan_irq", self);
259 if (WARN_ON(ret < 0))
262 ret = enable_irq_wake(self->func->irq);
269 free_irq(self->func->irq, self);
274 static int cw1200_spi_irq_unsubscribe(struct hwbus_priv *self)
276 pr_debug("SW IRQ unsubscribe\n");
277 disable_irq_wake(self->func->irq);
278 free_irq(self->func->irq, self);
283 static int cw1200_spi_irq_enable(struct hwbus_priv *self, int enable)
285 /* Disables are handled by the interrupt handler */
286 if (enable && self->irq_disabled) {
287 enable_irq(self->func->irq);
288 self->irq_disabled = 0;
294 static int cw1200_spi_off(const struct cw1200_platform_data_spi *pdata)
297 gpio_set_value(pdata->reset, 0);
298 msleep(30); /* Min is 2 * CLK32K cycles */
299 gpio_free(pdata->reset);
302 if (pdata->power_ctrl)
303 pdata->power_ctrl(pdata, false);
305 pdata->clk_ctrl(pdata, false);
310 static int cw1200_spi_on(const struct cw1200_platform_data_spi *pdata)
312 /* Ensure I/Os are pulled low */
314 gpio_request(pdata->reset, "cw1200_wlan_reset");
315 gpio_direction_output(pdata->reset, 0);
317 if (pdata->powerup) {
318 gpio_request(pdata->powerup, "cw1200_wlan_powerup");
319 gpio_direction_output(pdata->powerup, 0);
321 if (pdata->reset || pdata->powerup)
322 msleep(10); /* Settle time? */
324 /* Enable 3v3 and 1v8 to hardware */
325 if (pdata->power_ctrl) {
326 if (pdata->power_ctrl(pdata, true)) {
327 pr_err("power_ctrl() failed!\n");
333 if (pdata->clk_ctrl) {
334 if (pdata->clk_ctrl(pdata, true)) {
335 pr_err("clk_ctrl() failed!\n");
338 msleep(10); /* Delay until clock is stable for 2 cycles */
341 /* Enable POWERUP signal */
342 if (pdata->powerup) {
343 gpio_set_value(pdata->powerup, 1);
344 msleep(250); /* or more..? */
346 /* Enable RSTn signal */
348 gpio_set_value(pdata->reset, 1);
349 msleep(50); /* Or more..? */
354 static size_t cw1200_spi_align_size(struct hwbus_priv *self, size_t size)
356 return size & 1 ? size + 1 : size;
359 static int cw1200_spi_pm(struct hwbus_priv *self, bool suspend)
361 return irq_set_irq_wake(self->func->irq, suspend);
364 static struct hwbus_ops cw1200_spi_hwbus_ops = {
365 .hwbus_memcpy_fromio = cw1200_spi_memcpy_fromio,
366 .hwbus_memcpy_toio = cw1200_spi_memcpy_toio,
367 .lock = cw1200_spi_lock,
368 .unlock = cw1200_spi_unlock,
369 .align_size = cw1200_spi_align_size,
370 .power_mgmt = cw1200_spi_pm,
371 .irq_enable = cw1200_spi_irq_enable,
374 /* Probe Function to be called by SPI stack when device is discovered */
375 static int cw1200_spi_probe(struct spi_device *func)
377 const struct cw1200_platform_data_spi *plat_data =
378 func->dev.platform_data;
379 struct hwbus_priv *self;
382 /* Sanity check speed */
383 if (func->max_speed_hz > 52000000)
384 func->max_speed_hz = 52000000;
385 if (func->max_speed_hz < 1000000)
386 func->max_speed_hz = 1000000;
388 /* Fix up transfer size */
389 if (plat_data->spi_bits_per_word)
390 func->bits_per_word = plat_data->spi_bits_per_word;
391 if (!func->bits_per_word)
392 func->bits_per_word = 16;
395 func->mode = SPI_MODE_0;
397 pr_info("cw1200_wlan_spi: Probe called (CS %d M %d BPW %d CLK %d)\n",
398 func->chip_select, func->mode, func->bits_per_word,
401 if (cw1200_spi_on(plat_data)) {
402 pr_err("spi_on() failed!\n");
406 if (spi_setup(func)) {
407 pr_err("spi_setup() failed!\n");
411 self = kzalloc(sizeof(*self), GFP_KERNEL);
413 pr_err("Can't allocate SPI hwbus_priv.");
417 self->pdata = plat_data;
419 spin_lock_init(&self->lock);
421 spi_set_drvdata(func, self);
423 init_waitqueue_head(&self->wq);
425 status = cw1200_spi_irq_subscribe(self);
427 status = cw1200_core_probe(&cw1200_spi_hwbus_ops,
428 self, &func->dev, &self->core,
429 self->pdata->ref_clk,
430 self->pdata->macaddr,
431 self->pdata->sdd_file,
432 self->pdata->have_5ghz);
435 cw1200_spi_irq_unsubscribe(self);
436 cw1200_spi_off(plat_data);
443 /* Disconnect Function to be called by SPI stack when device is disconnected */
444 static int cw1200_spi_disconnect(struct spi_device *func)
446 struct hwbus_priv *self = spi_get_drvdata(func);
449 cw1200_spi_irq_unsubscribe(self);
451 cw1200_core_release(self->core);
456 cw1200_spi_off(func->dev.platform_data);
462 static int cw1200_spi_suspend(struct device *dev, pm_message_t state)
464 struct hwbus_priv *self = spi_get_drvdata(to_spi_device(dev));
466 if (!cw1200_can_suspend(self->core))
469 /* XXX notify host that we have to keep CW1200 powered on? */
473 static int cw1200_spi_resume(struct device *dev)
479 static struct spi_driver spi_driver = {
480 .probe = cw1200_spi_probe,
481 .remove = cw1200_spi_disconnect,
483 .name = "cw1200_wlan_spi",
484 .bus = &spi_bus_type,
485 .owner = THIS_MODULE,
487 .suspend = cw1200_spi_suspend,
488 .resume = cw1200_spi_resume,
493 module_spi_driver(spi_driver);