Linux Audio

Check our new training course

Loading...
Note: File does not exist in v6.13.7.
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Synaptics NavPoint (PXA27x SSP/SPI) driver.
  4 *
  5 * Copyright (C) 2012 Paul Parsons <lost.distance@yahoo.com>
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/platform_device.h>
 11#include <linux/clk.h>
 12#include <linux/delay.h>
 13#include <linux/gpio/consumer.h>
 14#include <linux/input.h>
 15#include <linux/input/navpoint.h>
 16#include <linux/interrupt.h>
 17#include <linux/mutex.h>
 18#include <linux/pxa2xx_ssp.h>
 19#include <linux/slab.h>
 20
 21/*
 22 * Synaptics Modular Embedded Protocol: Module Packet Format.
 23 * Module header byte 2:0 = Length (# bytes that follow)
 24 * Module header byte 4:3 = Control
 25 * Module header byte 7:5 = Module Address
 26 */
 27#define HEADER_LENGTH(byte)	((byte) & 0x07)
 28#define HEADER_CONTROL(byte)	(((byte) >> 3) & 0x03)
 29#define HEADER_ADDRESS(byte)	((byte) >> 5)
 30
 31struct navpoint {
 32	struct ssp_device	*ssp;
 33	struct input_dev	*input;
 34	struct device		*dev;
 35	struct gpio_desc	*gpiod;
 36	int			index;
 37	u8			data[1 + HEADER_LENGTH(0xff)];
 38};
 39
 40/*
 41 * Initialization values for SSCR0_x, SSCR1_x, SSSR_x.
 42 */
 43static const u32 sscr0 = 0
 44	| SSCR0_TUM		/* TIM = 1; No TUR interrupts */
 45	| SSCR0_RIM		/* RIM = 1; No ROR interrupts */
 46	| SSCR0_SSE		/* SSE = 1; SSP enabled */
 47	| SSCR0_Motorola	/* FRF = 0; Motorola SPI */
 48	| SSCR0_DataSize(16)	/* DSS = 15; Data size = 16-bit */
 49	;
 50static const u32 sscr1 = 0
 51	| SSCR1_SCFR		/* SCFR = 1; SSPSCLK only during transfers */
 52	| SSCR1_SCLKDIR		/* SCLKDIR = 1; Slave mode */
 53	| SSCR1_SFRMDIR		/* SFRMDIR = 1; Slave mode */
 54	| SSCR1_RWOT		/* RWOT = 1; Receive without transmit mode */
 55	| SSCR1_RxTresh(1)	/* RFT = 0; Receive FIFO threshold = 1 */
 56	| SSCR1_SPH		/* SPH = 1; SSPSCLK inactive 0.5 + 1 cycles */
 57	| SSCR1_RIE		/* RIE = 1; Receive FIFO interrupt enabled */
 58	;
 59static const u32 sssr = 0
 60	| SSSR_BCE		/* BCE = 1; Clear BCE */
 61	| SSSR_TUR		/* TUR = 1; Clear TUR */
 62	| SSSR_EOC		/* EOC = 1; Clear EOC */
 63	| SSSR_TINT		/* TINT = 1; Clear TINT */
 64	| SSSR_PINT		/* PINT = 1; Clear PINT */
 65	| SSSR_ROR		/* ROR = 1; Clear ROR */
 66	;
 67
 68/*
 69 * MEP Query $22: Touchpad Coordinate Range Query is not supported by
 70 * the NavPoint module, so sampled values provide the default limits.
 71 */
 72#define NAVPOINT_X_MIN		1278
 73#define NAVPOINT_X_MAX		5340
 74#define NAVPOINT_Y_MIN		1572
 75#define NAVPOINT_Y_MAX		4396
 76#define NAVPOINT_PRESSURE_MIN	0
 77#define NAVPOINT_PRESSURE_MAX	255
 78
 79static void navpoint_packet(struct navpoint *navpoint)
 80{
 81	int finger;
 82	int gesture;
 83	int x, y, z;
 84
 85	switch (navpoint->data[0]) {
 86	case 0xff:	/* Garbage (packet?) between reset and Hello packet */
 87	case 0x00:	/* Module 0, NULL packet */
 88		break;
 89
 90	case 0x0e:	/* Module 0, Absolute packet */
 91		finger = (navpoint->data[1] & 0x01);
 92		gesture = (navpoint->data[1] & 0x02);
 93		x = ((navpoint->data[2] & 0x1f) << 8) | navpoint->data[3];
 94		y = ((navpoint->data[4] & 0x1f) << 8) | navpoint->data[5];
 95		z = navpoint->data[6];
 96		input_report_key(navpoint->input, BTN_TOUCH, finger);
 97		input_report_abs(navpoint->input, ABS_X, x);
 98		input_report_abs(navpoint->input, ABS_Y, y);
 99		input_report_abs(navpoint->input, ABS_PRESSURE, z);
100		input_report_key(navpoint->input, BTN_TOOL_FINGER, finger);
101		input_report_key(navpoint->input, BTN_LEFT, gesture);
102		input_sync(navpoint->input);
103		break;
104
105	case 0x19:	/* Module 0, Hello packet */
106		if ((navpoint->data[1] & 0xf0) == 0x10)
107			break;
108		fallthrough;
109	default:
110		dev_warn(navpoint->dev,
111			 "spurious packet: data=0x%02x,0x%02x,...\n",
112			 navpoint->data[0], navpoint->data[1]);
113		break;
114	}
115}
116
117static irqreturn_t navpoint_irq(int irq, void *dev_id)
118{
119	struct navpoint *navpoint = dev_id;
120	struct ssp_device *ssp = navpoint->ssp;
121	irqreturn_t ret = IRQ_NONE;
122	u32 status;
123
124	status = pxa_ssp_read_reg(ssp, SSSR);
125	if (status & sssr) {
126		dev_warn(navpoint->dev,
127			 "unexpected interrupt: status=0x%08x\n", status);
128		pxa_ssp_write_reg(ssp, SSSR, (status & sssr));
129		ret = IRQ_HANDLED;
130	}
131
132	while (status & SSSR_RNE) {
133		u32 data;
134
135		data = pxa_ssp_read_reg(ssp, SSDR);
136		navpoint->data[navpoint->index + 0] = (data >> 8);
137		navpoint->data[navpoint->index + 1] = data;
138		navpoint->index += 2;
139		if (HEADER_LENGTH(navpoint->data[0]) < navpoint->index) {
140			navpoint_packet(navpoint);
141			navpoint->index = 0;
142		}
143		status = pxa_ssp_read_reg(ssp, SSSR);
144		ret = IRQ_HANDLED;
145	}
146
147	return ret;
148}
149
150static void navpoint_up(struct navpoint *navpoint)
151{
152	struct ssp_device *ssp = navpoint->ssp;
153	int timeout;
154
155	clk_prepare_enable(ssp->clk);
156
157	pxa_ssp_write_reg(ssp, SSCR1, sscr1);
158	pxa_ssp_write_reg(ssp, SSSR, sssr);
159	pxa_ssp_write_reg(ssp, SSTO, 0);
160	pxa_ssp_write_reg(ssp, SSCR0, sscr0);	/* SSCR0_SSE written last */
161
162	/* Wait until SSP port is ready for slave clock operations */
163	for (timeout = 100; timeout != 0; --timeout) {
164		if (!(pxa_ssp_read_reg(ssp, SSSR) & SSSR_CSS))
165			break;
166		msleep(1);
167	}
168
169	if (timeout == 0)
170		dev_err(navpoint->dev,
171			"timeout waiting for SSSR[CSS] to clear\n");
172
173	gpiod_set_value(navpoint->gpiod, 1);
174}
175
176static void navpoint_down(struct navpoint *navpoint)
177{
178	struct ssp_device *ssp = navpoint->ssp;
179
180	gpiod_set_value(navpoint->gpiod, 0);
181
182	pxa_ssp_write_reg(ssp, SSCR0, 0);
183
184	clk_disable_unprepare(ssp->clk);
185}
186
187static int navpoint_open(struct input_dev *input)
188{
189	struct navpoint *navpoint = input_get_drvdata(input);
190
191	navpoint_up(navpoint);
192
193	return 0;
194}
195
196static void navpoint_close(struct input_dev *input)
197{
198	struct navpoint *navpoint = input_get_drvdata(input);
199
200	navpoint_down(navpoint);
201}
202
203static int navpoint_probe(struct platform_device *pdev)
204{
205	const struct navpoint_platform_data *pdata =
206					dev_get_platdata(&pdev->dev);
207	struct ssp_device *ssp;
208	struct input_dev *input;
209	struct navpoint *navpoint;
210	int error;
211
212	if (!pdata) {
213		dev_err(&pdev->dev, "no platform data\n");
214		return -EINVAL;
215	}
216
217	ssp = pxa_ssp_request(pdata->port, pdev->name);
218	if (!ssp)
219		return -ENODEV;
220
221	/* HaRET does not disable devices before jumping into Linux */
222	if (pxa_ssp_read_reg(ssp, SSCR0) & SSCR0_SSE) {
223		pxa_ssp_write_reg(ssp, SSCR0, 0);
224		dev_warn(&pdev->dev, "ssp%d already enabled\n", pdata->port);
225	}
226
227	navpoint = kzalloc(sizeof(*navpoint), GFP_KERNEL);
228	input = input_allocate_device();
229	if (!navpoint || !input) {
230		error = -ENOMEM;
231		goto err_free_mem;
232	}
233
234	navpoint->gpiod = gpiod_get_optional(&pdev->dev,
235					     NULL, GPIOD_OUT_LOW);
236	if (IS_ERR(navpoint->gpiod)) {
237		error = PTR_ERR(navpoint->gpiod);
238		dev_err(&pdev->dev, "error getting GPIO\n");
239		goto err_free_mem;
240	}
241	gpiod_set_consumer_name(navpoint->gpiod, "SYNAPTICS_ON");
242
243	navpoint->ssp = ssp;
244	navpoint->input = input;
245	navpoint->dev = &pdev->dev;
246
247	input->name = pdev->name;
248	input->dev.parent = &pdev->dev;
249
250	__set_bit(EV_KEY, input->evbit);
251	__set_bit(EV_ABS, input->evbit);
252	__set_bit(BTN_LEFT, input->keybit);
253	__set_bit(BTN_TOUCH, input->keybit);
254	__set_bit(BTN_TOOL_FINGER, input->keybit);
255
256	input_set_abs_params(input, ABS_X,
257			     NAVPOINT_X_MIN, NAVPOINT_X_MAX, 0, 0);
258	input_set_abs_params(input, ABS_Y,
259			     NAVPOINT_Y_MIN, NAVPOINT_Y_MAX, 0, 0);
260	input_set_abs_params(input, ABS_PRESSURE,
261			     NAVPOINT_PRESSURE_MIN, NAVPOINT_PRESSURE_MAX,
262			     0, 0);
263
264	input->open = navpoint_open;
265	input->close = navpoint_close;
266
267	input_set_drvdata(input, navpoint);
268
269	error = request_irq(ssp->irq, navpoint_irq, 0, pdev->name, navpoint);
270	if (error)
271		goto err_free_mem;
272
273	error = input_register_device(input);
274	if (error)
275		goto err_free_irq;
276
277	platform_set_drvdata(pdev, navpoint);
278	dev_dbg(&pdev->dev, "ssp%d, irq %d\n", pdata->port, ssp->irq);
279
280	return 0;
281
282err_free_irq:
283	free_irq(ssp->irq, navpoint);
284err_free_mem:
285	input_free_device(input);
286	kfree(navpoint);
287	pxa_ssp_free(ssp);
288
289	return error;
290}
291
292static void navpoint_remove(struct platform_device *pdev)
293{
294	struct navpoint *navpoint = platform_get_drvdata(pdev);
295	struct ssp_device *ssp = navpoint->ssp;
296
297	free_irq(ssp->irq, navpoint);
298
299	input_unregister_device(navpoint->input);
300	kfree(navpoint);
301
302	pxa_ssp_free(ssp);
303}
304
305static int navpoint_suspend(struct device *dev)
306{
307	struct platform_device *pdev = to_platform_device(dev);
308	struct navpoint *navpoint = platform_get_drvdata(pdev);
309	struct input_dev *input = navpoint->input;
310
311	mutex_lock(&input->mutex);
312	if (input_device_enabled(input))
313		navpoint_down(navpoint);
314	mutex_unlock(&input->mutex);
315
316	return 0;
317}
318
319static int navpoint_resume(struct device *dev)
320{
321	struct platform_device *pdev = to_platform_device(dev);
322	struct navpoint *navpoint = platform_get_drvdata(pdev);
323	struct input_dev *input = navpoint->input;
324
325	mutex_lock(&input->mutex);
326	if (input_device_enabled(input))
327		navpoint_up(navpoint);
328	mutex_unlock(&input->mutex);
329
330	return 0;
331}
332
333static DEFINE_SIMPLE_DEV_PM_OPS(navpoint_pm_ops,
334				navpoint_suspend, navpoint_resume);
335
336static struct platform_driver navpoint_driver = {
337	.probe		= navpoint_probe,
338	.remove_new	= navpoint_remove,
339	.driver = {
340		.name	= "navpoint",
341		.pm	= pm_sleep_ptr(&navpoint_pm_ops),
342	},
343};
344
345module_platform_driver(navpoint_driver);
346
347MODULE_AUTHOR("Paul Parsons <lost.distance@yahoo.com>");
348MODULE_DESCRIPTION("Synaptics NavPoint (PXA27x SSP/SPI) driver");
349MODULE_LICENSE("GPL");
350MODULE_ALIAS("platform:navpoint");