1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * This file is part of wl1251
  4 *
  5 * Copyright (C) 2008 Nokia Corporation
  6 */
  7
  8#include <linux/err.h>
  9#include <linux/interrupt.h>
 10#include <linux/irq.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/swab.h>
 14#include <linux/crc7.h>
 15#include <linux/spi/spi.h>
 16#include <linux/gpio/consumer.h>
 17#include <linux/of.h>
 18#include <linux/regulator/consumer.h>
 19
 20#include "wl1251.h"
 21#include "reg.h"
 22#include "spi.h"
 23
 24struct wl1251_spi {
 25	struct spi_device *spi;
 26	struct gpio_desc *power_gpio;
 27};
 28
 29static irqreturn_t wl1251_irq(int irq, void *cookie)
 30{
 31	struct wl1251 *wl;
 32
 33	wl1251_debug(DEBUG_IRQ, "IRQ");
 34
 35	wl = cookie;
 36
 37	ieee80211_queue_work(wl->hw, &wl->irq_work);
 38
 39	return IRQ_HANDLED;
 40}
 41
 42static void wl1251_spi_reset(struct wl1251 *wl)
 43{
 44	struct wl1251_spi *wl_spi = wl->if_priv;
 45	u8 *cmd;
 46	struct spi_transfer t;
 47	struct spi_message m;
 48
 49	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 50	if (!cmd) {
 51		wl1251_error("could not allocate cmd for spi reset");
 52		return;
 53	}
 54
 55	memset(&t, 0, sizeof(t));
 56	spi_message_init(&m);
 57
 58	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 59
 60	t.tx_buf = cmd;
 61	t.len = WSPI_INIT_CMD_LEN;
 62	spi_message_add_tail(&t, &m);
 63
 64	spi_sync(wl_spi->spi, &m);
 65
 66	wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 67
 68	kfree(cmd);
 69}
 70
 71static void wl1251_spi_wake(struct wl1251 *wl)
 72{
 73	struct wl1251_spi *wl_spi = wl->if_priv;
 74	struct spi_transfer t;
 75	struct spi_message m;
 76	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 77
 78	if (!cmd) {
 79		wl1251_error("could not allocate cmd for spi init");
 80		return;
 81	}
 82
 83	memset(&t, 0, sizeof(t));
 84	spi_message_init(&m);
 85
 86	/* Set WSPI_INIT_COMMAND
 87	 * the data is being send from the MSB to LSB
 88	 */
 89	cmd[0] = 0xff;
 90	cmd[1] = 0xff;
 91	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 92	cmd[3] = 0;
 93	cmd[4] = 0;
 94	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 95	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 96
 97	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 98		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 99
100	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
101		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
102	else
103		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
104
105	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
106	/*
107	 * The above is the logical order; it must actually be stored
108	 * in the buffer byte-swapped.
109	 */
110	__swab32s((u32 *)cmd);
111	__swab32s((u32 *)cmd+1);
112
113	t.tx_buf = cmd;
114	t.len = WSPI_INIT_CMD_LEN;
115	spi_message_add_tail(&t, &m);
116
117	spi_sync(wl_spi->spi, &m);
118
119	wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
120
121	kfree(cmd);
122}
123
124static void wl1251_spi_reset_wake(struct wl1251 *wl)
125{
126	wl1251_spi_reset(wl);
127	wl1251_spi_wake(wl);
128}
129
130static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
131			    size_t len)
132{
133	struct wl1251_spi *wl_spi = wl->if_priv;
134	struct spi_transfer t[3];
135	struct spi_message m;
136	u8 *busy_buf;
137	u32 *cmd;
138
139	cmd = &wl->buffer_cmd;
140	busy_buf = wl->buffer_busyword;
141
142	*cmd = 0;
143	*cmd |= WSPI_CMD_READ;
144	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
145	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
146
147	spi_message_init(&m);
148	memset(t, 0, sizeof(t));
149
150	t[0].tx_buf = cmd;
151	t[0].len = 4;
152	spi_message_add_tail(&t[0], &m);
153
154	/* Busy and non busy words read */
155	t[1].rx_buf = busy_buf;
156	t[1].len = WL1251_BUSY_WORD_LEN;
157	spi_message_add_tail(&t[1], &m);
158
159	t[2].rx_buf = buf;
160	t[2].len = len;
161	spi_message_add_tail(&t[2], &m);
162
163	spi_sync(wl_spi->spi, &m);
164
165	/* FIXME: check busy words */
166
167	wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
168	wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
169}
170
171static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
172			     size_t len)
173{
174	struct wl1251_spi *wl_spi = wl->if_priv;
175	struct spi_transfer t[2];
176	struct spi_message m;
177	u32 *cmd;
178
179	cmd = &wl->buffer_cmd;
180
181	*cmd = 0;
182	*cmd |= WSPI_CMD_WRITE;
183	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
184	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
185
186	spi_message_init(&m);
187	memset(t, 0, sizeof(t));
188
189	t[0].tx_buf = cmd;
190	t[0].len = sizeof(*cmd);
191	spi_message_add_tail(&t[0], &m);
192
193	t[1].tx_buf = buf;
194	t[1].len = len;
195	spi_message_add_tail(&t[1], &m);
196
197	spi_sync(wl_spi->spi, &m);
198
199	wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
200	wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
201}
202
203static void wl1251_spi_enable_irq(struct wl1251 *wl)
204{
205	return enable_irq(wl->irq);
206}
207
208static void wl1251_spi_disable_irq(struct wl1251 *wl)
209{
210	return disable_irq(wl->irq);
211}
212
213static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
214{
215	struct wl1251_spi *wl_spi = wl->if_priv;
216
217	if (wl_spi->power_gpio)
218		gpiod_set_value_cansleep(wl_spi->power_gpio, enable);
219
220	return 0;
221}
222
223static const struct wl1251_if_operations wl1251_spi_ops = {
224	.read = wl1251_spi_read,
225	.write = wl1251_spi_write,
226	.reset = wl1251_spi_reset_wake,
227	.enable_irq = wl1251_spi_enable_irq,
228	.disable_irq = wl1251_spi_disable_irq,
229	.power = wl1251_spi_set_power,
230};
231
232static int wl1251_spi_probe(struct spi_device *spi)
233{
234	struct device_node *np = spi->dev.of_node;
235	struct ieee80211_hw *hw;
236	struct wl1251_spi *wl_spi;
237	struct wl1251 *wl;
238	int ret;
239
240	if (!np)
241		return -ENODEV;
242
243	wl_spi = devm_kzalloc(&spi->dev, sizeof(*wl_spi), GFP_KERNEL);
244	if (!wl_spi)
245		return -ENOMEM;
246
247	wl_spi->spi = spi;
248
249	hw = wl1251_alloc_hw();
250	if (IS_ERR(hw))
251		return PTR_ERR(hw);
252
253	wl = hw->priv;
254
255	SET_IEEE80211_DEV(hw, &spi->dev);
256	spi_set_drvdata(spi, wl);
257	wl->if_priv = wl_spi;
258	wl->if_ops = &wl1251_spi_ops;
259
260	/* This is the only SPI value that we need to set here, the rest
261	 * comes from the board-peripherals file
262	 */
263	spi->bits_per_word = 32;
264
265	ret = spi_setup(spi);
266	if (ret < 0) {
267		wl1251_error("spi_setup failed");
268		goto out_free;
269	}
270
271	wl->use_eeprom = of_property_read_bool(np, "ti,wl1251-has-eeprom");
272
273	wl_spi->power_gpio = devm_gpiod_get_optional(&spi->dev, "ti,power",
274						     GPIOD_OUT_LOW);
275	ret = PTR_ERR_OR_ZERO(wl_spi->power_gpio);
276	if (ret) {
277		if (ret != -EPROBE_DEFER)
278			wl1251_error("Failed to request gpio: %d\n", ret);
279		goto out_free;
280	}
281
282	gpiod_set_consumer_name(wl_spi->power_gpio, "wl1251 power");
283
284	wl->irq = spi->irq;
285	if (wl->irq < 0) {
286		wl1251_error("irq missing in platform data");
287		ret = -ENODEV;
288		goto out_free;
289	}
290
291	irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
292	ret = devm_request_irq(&spi->dev, wl->irq, wl1251_irq, 0,
293							DRIVER_NAME, wl);
294	if (ret < 0) {
295		wl1251_error("request_irq() failed: %d", ret);
296		goto out_free;
297	}
298
299	irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
300
301	wl->vio = devm_regulator_get(&spi->dev, "vio");
302	if (IS_ERR(wl->vio)) {
303		ret = PTR_ERR(wl->vio);
304		wl1251_error("vio regulator missing: %d", ret);
305		goto out_free;
306	}
307
308	ret = regulator_enable(wl->vio);
309	if (ret)
310		goto out_free;
311
312	ret = wl1251_init_ieee80211(wl);
313	if (ret)
314		goto disable_regulator;
315
316	return 0;
317
318disable_regulator:
319	regulator_disable(wl->vio);
320out_free:
321	ieee80211_free_hw(hw);
322
323	return ret;
324}
325
326static void wl1251_spi_remove(struct spi_device *spi)
327{
328	struct wl1251 *wl = spi_get_drvdata(spi);
329
330	wl1251_free_hw(wl);
331	regulator_disable(wl->vio);
332}
333
334static struct spi_driver wl1251_spi_driver = {
335	.driver = {
336		.name		= DRIVER_NAME,
337	},
338
339	.probe		= wl1251_spi_probe,
340	.remove		= wl1251_spi_remove,
341};
342
343module_spi_driver(wl1251_spi_driver);
344
345MODULE_DESCRIPTION("TI WL1251 SPI helpers");
346MODULE_LICENSE("GPL");
347MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
348MODULE_ALIAS("spi:wl1251");