xref: /openbmc/linux/drivers/input/mouse/navpoint.c (revision 0ca5bc95)
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.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 
31 struct navpoint {
32 	struct ssp_device	*ssp;
33 	struct input_dev	*input;
34 	struct device		*dev;
35 	int			gpio;
36 	int			index;
37 	u8			data[1 + HEADER_LENGTH(0xff)];
38 };
39 
40 /*
41  * Initialization values for SSCR0_x, SSCR1_x, SSSR_x.
42  */
43 static 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 	;
50 static 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 	;
59 static 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 
navpoint_packet(struct navpoint * navpoint)79 static 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 
navpoint_irq(int irq,void * dev_id)117 static 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 
navpoint_up(struct navpoint * navpoint)150 static 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 	if (gpio_is_valid(navpoint->gpio))
174 		gpio_set_value(navpoint->gpio, 1);
175 }
176 
navpoint_down(struct navpoint * navpoint)177 static void navpoint_down(struct navpoint *navpoint)
178 {
179 	struct ssp_device *ssp = navpoint->ssp;
180 
181 	if (gpio_is_valid(navpoint->gpio))
182 		gpio_set_value(navpoint->gpio, 0);
183 
184 	pxa_ssp_write_reg(ssp, SSCR0, 0);
185 
186 	clk_disable_unprepare(ssp->clk);
187 }
188 
navpoint_open(struct input_dev * input)189 static int navpoint_open(struct input_dev *input)
190 {
191 	struct navpoint *navpoint = input_get_drvdata(input);
192 
193 	navpoint_up(navpoint);
194 
195 	return 0;
196 }
197 
navpoint_close(struct input_dev * input)198 static void navpoint_close(struct input_dev *input)
199 {
200 	struct navpoint *navpoint = input_get_drvdata(input);
201 
202 	navpoint_down(navpoint);
203 }
204 
navpoint_probe(struct platform_device * pdev)205 static int navpoint_probe(struct platform_device *pdev)
206 {
207 	const struct navpoint_platform_data *pdata =
208 					dev_get_platdata(&pdev->dev);
209 	struct ssp_device *ssp;
210 	struct input_dev *input;
211 	struct navpoint *navpoint;
212 	int error;
213 
214 	if (!pdata) {
215 		dev_err(&pdev->dev, "no platform data\n");
216 		return -EINVAL;
217 	}
218 
219 	if (gpio_is_valid(pdata->gpio)) {
220 		error = gpio_request_one(pdata->gpio, GPIOF_OUT_INIT_LOW,
221 					 "SYNAPTICS_ON");
222 		if (error)
223 			return error;
224 	}
225 
226 	ssp = pxa_ssp_request(pdata->port, pdev->name);
227 	if (!ssp) {
228 		error = -ENODEV;
229 		goto err_free_gpio;
230 	}
231 
232 	/* HaRET does not disable devices before jumping into Linux */
233 	if (pxa_ssp_read_reg(ssp, SSCR0) & SSCR0_SSE) {
234 		pxa_ssp_write_reg(ssp, SSCR0, 0);
235 		dev_warn(&pdev->dev, "ssp%d already enabled\n", pdata->port);
236 	}
237 
238 	navpoint = kzalloc(sizeof(*navpoint), GFP_KERNEL);
239 	input = input_allocate_device();
240 	if (!navpoint || !input) {
241 		error = -ENOMEM;
242 		goto err_free_mem;
243 	}
244 
245 	navpoint->ssp = ssp;
246 	navpoint->input = input;
247 	navpoint->dev = &pdev->dev;
248 	navpoint->gpio = pdata->gpio;
249 
250 	input->name = pdev->name;
251 	input->dev.parent = &pdev->dev;
252 
253 	__set_bit(EV_KEY, input->evbit);
254 	__set_bit(EV_ABS, input->evbit);
255 	__set_bit(BTN_LEFT, input->keybit);
256 	__set_bit(BTN_TOUCH, input->keybit);
257 	__set_bit(BTN_TOOL_FINGER, input->keybit);
258 
259 	input_set_abs_params(input, ABS_X,
260 			     NAVPOINT_X_MIN, NAVPOINT_X_MAX, 0, 0);
261 	input_set_abs_params(input, ABS_Y,
262 			     NAVPOINT_Y_MIN, NAVPOINT_Y_MAX, 0, 0);
263 	input_set_abs_params(input, ABS_PRESSURE,
264 			     NAVPOINT_PRESSURE_MIN, NAVPOINT_PRESSURE_MAX,
265 			     0, 0);
266 
267 	input->open = navpoint_open;
268 	input->close = navpoint_close;
269 
270 	input_set_drvdata(input, navpoint);
271 
272 	error = request_irq(ssp->irq, navpoint_irq, 0, pdev->name, navpoint);
273 	if (error)
274 		goto err_free_mem;
275 
276 	error = input_register_device(input);
277 	if (error)
278 		goto err_free_irq;
279 
280 	platform_set_drvdata(pdev, navpoint);
281 	dev_dbg(&pdev->dev, "ssp%d, irq %d\n", pdata->port, ssp->irq);
282 
283 	return 0;
284 
285 err_free_irq:
286 	free_irq(ssp->irq, navpoint);
287 err_free_mem:
288 	input_free_device(input);
289 	kfree(navpoint);
290 	pxa_ssp_free(ssp);
291 err_free_gpio:
292 	if (gpio_is_valid(pdata->gpio))
293 		gpio_free(pdata->gpio);
294 
295 	return error;
296 }
297 
navpoint_remove(struct platform_device * pdev)298 static int navpoint_remove(struct platform_device *pdev)
299 {
300 	const struct navpoint_platform_data *pdata =
301 					dev_get_platdata(&pdev->dev);
302 	struct navpoint *navpoint = platform_get_drvdata(pdev);
303 	struct ssp_device *ssp = navpoint->ssp;
304 
305 	free_irq(ssp->irq, navpoint);
306 
307 	input_unregister_device(navpoint->input);
308 	kfree(navpoint);
309 
310 	pxa_ssp_free(ssp);
311 
312 	if (gpio_is_valid(pdata->gpio))
313 		gpio_free(pdata->gpio);
314 
315 	return 0;
316 }
317 
navpoint_suspend(struct device * dev)318 static int navpoint_suspend(struct device *dev)
319 {
320 	struct platform_device *pdev = to_platform_device(dev);
321 	struct navpoint *navpoint = platform_get_drvdata(pdev);
322 	struct input_dev *input = navpoint->input;
323 
324 	mutex_lock(&input->mutex);
325 	if (input_device_enabled(input))
326 		navpoint_down(navpoint);
327 	mutex_unlock(&input->mutex);
328 
329 	return 0;
330 }
331 
navpoint_resume(struct device * dev)332 static int navpoint_resume(struct device *dev)
333 {
334 	struct platform_device *pdev = to_platform_device(dev);
335 	struct navpoint *navpoint = platform_get_drvdata(pdev);
336 	struct input_dev *input = navpoint->input;
337 
338 	mutex_lock(&input->mutex);
339 	if (input_device_enabled(input))
340 		navpoint_up(navpoint);
341 	mutex_unlock(&input->mutex);
342 
343 	return 0;
344 }
345 
346 static DEFINE_SIMPLE_DEV_PM_OPS(navpoint_pm_ops,
347 				navpoint_suspend, navpoint_resume);
348 
349 static struct platform_driver navpoint_driver = {
350 	.probe		= navpoint_probe,
351 	.remove		= navpoint_remove,
352 	.driver = {
353 		.name	= "navpoint",
354 		.pm	= pm_sleep_ptr(&navpoint_pm_ops),
355 	},
356 };
357 
358 module_platform_driver(navpoint_driver);
359 
360 MODULE_AUTHOR("Paul Parsons <lost.distance@yahoo.com>");
361 MODULE_DESCRIPTION("Synaptics NavPoint (PXA27x SSP/SPI) driver");
362 MODULE_LICENSE("GPL");
363 MODULE_ALIAS("platform:navpoint");
364