1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LCD/Backlight Driver for Sharp Zaurus Handhelds (various models)
4 *
5 * Copyright (c) 2004-2006 Richard Purdie
6 *
7 * Based on Sharp's 2.4 Backlight Driver
8 *
9 * Copyright (c) 2008 Marvell International Ltd.
10 * Converted to SPI device based LCD/Backlight device driver
11 * by Eric Miao <eric.miao@marvell.com>
12 */
13
14#include <linux/backlight.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/delay.h>
19#include <linux/gpio/consumer.h>
20#include <linux/fb.h>
21#include <linux/lcd.h>
22#include <linux/spi/spi.h>
23#include <linux/spi/corgi_lcd.h>
24#include <linux/slab.h>
25#include <asm/mach/sharpsl_param.h>
26
27#define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL)
28
29/* Register Addresses */
30#define RESCTL_ADRS 0x00
31#define PHACTRL_ADRS 0x01
32#define DUTYCTRL_ADRS 0x02
33#define POWERREG0_ADRS 0x03
34#define POWERREG1_ADRS 0x04
35#define GPOR3_ADRS 0x05
36#define PICTRL_ADRS 0x06
37#define POLCTRL_ADRS 0x07
38
39/* Register Bit Definitions */
40#define RESCTL_QVGA 0x01
41#define RESCTL_VGA 0x00
42
43#define POWER1_VW_ON 0x01 /* VW Supply FET ON */
44#define POWER1_GVSS_ON 0x02 /* GVSS(-8V) Power Supply ON */
45#define POWER1_VDD_ON 0x04 /* VDD(8V),SVSS(-4V) Power Supply ON */
46
47#define POWER1_VW_OFF 0x00 /* VW Supply FET OFF */
48#define POWER1_GVSS_OFF 0x00 /* GVSS(-8V) Power Supply OFF */
49#define POWER1_VDD_OFF 0x00 /* VDD(8V),SVSS(-4V) Power Supply OFF */
50
51#define POWER0_COM_DCLK 0x01 /* COM Voltage DC Bias DAC Serial Data Clock */
52#define POWER0_COM_DOUT 0x02 /* COM Voltage DC Bias DAC Serial Data Out */
53#define POWER0_DAC_ON 0x04 /* DAC Power Supply ON */
54#define POWER0_COM_ON 0x08 /* COM Power Supply ON */
55#define POWER0_VCC5_ON 0x10 /* VCC5 Power Supply ON */
56
57#define POWER0_DAC_OFF 0x00 /* DAC Power Supply OFF */
58#define POWER0_COM_OFF 0x00 /* COM Power Supply OFF */
59#define POWER0_VCC5_OFF 0x00 /* VCC5 Power Supply OFF */
60
61#define PICTRL_INIT_STATE 0x01
62#define PICTRL_INIOFF 0x02
63#define PICTRL_POWER_DOWN 0x04
64#define PICTRL_COM_SIGNAL_OFF 0x08
65#define PICTRL_DAC_SIGNAL_OFF 0x10
66
67#define POLCTRL_SYNC_POL_FALL 0x01
68#define POLCTRL_EN_POL_FALL 0x02
69#define POLCTRL_DATA_POL_FALL 0x04
70#define POLCTRL_SYNC_ACT_H 0x08
71#define POLCTRL_EN_ACT_L 0x10
72
73#define POLCTRL_SYNC_POL_RISE 0x00
74#define POLCTRL_EN_POL_RISE 0x00
75#define POLCTRL_DATA_POL_RISE 0x00
76#define POLCTRL_SYNC_ACT_L 0x00
77#define POLCTRL_EN_ACT_H 0x00
78
79#define PHACTRL_PHASE_MANUAL 0x01
80#define DEFAULT_PHAD_QVGA (9)
81#define DEFAULT_COMADJ (125)
82
83struct corgi_lcd {
84 struct spi_device *spi_dev;
85 struct lcd_device *lcd_dev;
86 struct backlight_device *bl_dev;
87
88 int limit_mask;
89 int intensity;
90 int power;
91 int mode;
92 char buf[2];
93
94 struct gpio_desc *backlight_on;
95 struct gpio_desc *backlight_cont;
96
97 void (*kick_battery)(void);
98};
99
100static int corgi_ssp_lcdtg_send(struct corgi_lcd *lcd, int reg, uint8_t val);
101
102static struct corgi_lcd *the_corgi_lcd;
103static unsigned long corgibl_flags;
104#define CORGIBL_SUSPENDED 0x01
105#define CORGIBL_BATTLOW 0x02
106
107/*
108 * This is only a pseudo I2C interface. We can't use the standard kernel
109 * routines as the interface is write only. We just assume the data is acked...
110 */
111static void lcdtg_ssp_i2c_send(struct corgi_lcd *lcd, uint8_t data)
112{
113 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS, val: data);
114 udelay(10);
115}
116
117static void lcdtg_i2c_send_bit(struct corgi_lcd *lcd, uint8_t data)
118{
119 lcdtg_ssp_i2c_send(lcd, data);
120 lcdtg_ssp_i2c_send(lcd, data: data | POWER0_COM_DCLK);
121 lcdtg_ssp_i2c_send(lcd, data);
122}
123
124static void lcdtg_i2c_send_start(struct corgi_lcd *lcd, uint8_t base)
125{
126 lcdtg_ssp_i2c_send(lcd, data: base | POWER0_COM_DCLK | POWER0_COM_DOUT);
127 lcdtg_ssp_i2c_send(lcd, data: base | POWER0_COM_DCLK);
128 lcdtg_ssp_i2c_send(lcd, data: base);
129}
130
131static void lcdtg_i2c_send_stop(struct corgi_lcd *lcd, uint8_t base)
132{
133 lcdtg_ssp_i2c_send(lcd, data: base);
134 lcdtg_ssp_i2c_send(lcd, data: base | POWER0_COM_DCLK);
135 lcdtg_ssp_i2c_send(lcd, data: base | POWER0_COM_DCLK | POWER0_COM_DOUT);
136}
137
138static void lcdtg_i2c_send_byte(struct corgi_lcd *lcd,
139 uint8_t base, uint8_t data)
140{
141 int i;
142
143 for (i = 0; i < 8; i++) {
144 if (data & 0x80)
145 lcdtg_i2c_send_bit(lcd, data: base | POWER0_COM_DOUT);
146 else
147 lcdtg_i2c_send_bit(lcd, data: base);
148 data <<= 1;
149 }
150}
151
152static void lcdtg_i2c_wait_ack(struct corgi_lcd *lcd, uint8_t base)
153{
154 lcdtg_i2c_send_bit(lcd, data: base);
155}
156
157static void lcdtg_set_common_voltage(struct corgi_lcd *lcd,
158 uint8_t base_data, uint8_t data)
159{
160 /* Set Common Voltage to M62332FP via I2C */
161 lcdtg_i2c_send_start(lcd, base: base_data);
162 lcdtg_i2c_send_byte(lcd, base: base_data, data: 0x9c);
163 lcdtg_i2c_wait_ack(lcd, base: base_data);
164 lcdtg_i2c_send_byte(lcd, base: base_data, data: 0x00);
165 lcdtg_i2c_wait_ack(lcd, base: base_data);
166 lcdtg_i2c_send_byte(lcd, base: base_data, data);
167 lcdtg_i2c_wait_ack(lcd, base: base_data);
168 lcdtg_i2c_send_stop(lcd, base: base_data);
169}
170
171static int corgi_ssp_lcdtg_send(struct corgi_lcd *lcd, int adrs, uint8_t data)
172{
173 struct spi_message msg;
174 struct spi_transfer xfer = {
175 .len = 1,
176 .cs_change = 0,
177 .tx_buf = lcd->buf,
178 };
179
180 lcd->buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
181 spi_message_init(m: &msg);
182 spi_message_add_tail(t: &xfer, m: &msg);
183
184 return spi_sync(spi: lcd->spi_dev, message: &msg);
185}
186
187/* Set Phase Adjust */
188static void lcdtg_set_phadadj(struct corgi_lcd *lcd, int mode)
189{
190 int adj;
191
192 switch (mode) {
193 case CORGI_LCD_MODE_VGA:
194 /* Setting for VGA */
195 adj = sharpsl_param.phadadj;
196 adj = (adj < 0) ? PHACTRL_PHASE_MANUAL :
197 PHACTRL_PHASE_MANUAL | ((adj & 0xf) << 1);
198 break;
199 case CORGI_LCD_MODE_QVGA:
200 default:
201 /* Setting for QVGA */
202 adj = (DEFAULT_PHAD_QVGA << 1) | PHACTRL_PHASE_MANUAL;
203 break;
204 }
205
206 corgi_ssp_lcdtg_send(lcd, PHACTRL_ADRS, data: adj);
207}
208
209static void corgi_lcd_power_on(struct corgi_lcd *lcd)
210{
211 int comadj;
212
213 /* Initialize Internal Logic & Port */
214 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
215 PICTRL_POWER_DOWN | PICTRL_INIOFF |
216 PICTRL_INIT_STATE | PICTRL_COM_SIGNAL_OFF |
217 PICTRL_DAC_SIGNAL_OFF);
218
219 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
220 POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_OFF |
221 POWER0_COM_OFF | POWER0_VCC5_OFF);
222
223 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
224 POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_OFF);
225
226 /* VDD(+8V), SVSS(-4V) ON */
227 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
228 POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_ON);
229 mdelay(3);
230
231 /* DAC ON */
232 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
233 POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
234 POWER0_COM_OFF | POWER0_VCC5_OFF);
235
236 /* INIB = H, INI = L */
237 /* PICTL[0] = H , PICTL[1] = PICTL[2] = PICTL[4] = L */
238 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
239 PICTRL_INIT_STATE | PICTRL_COM_SIGNAL_OFF);
240
241 /* Set Common Voltage */
242 comadj = sharpsl_param.comadj;
243 if (comadj < 0)
244 comadj = DEFAULT_COMADJ;
245
246 lcdtg_set_common_voltage(lcd, POWER0_DAC_ON | POWER0_COM_OFF |
247 POWER0_VCC5_OFF, data: comadj);
248
249 /* VCC5 ON, DAC ON */
250 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
251 POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
252 POWER0_COM_OFF | POWER0_VCC5_ON);
253
254 /* GVSS(-8V) ON, VDD ON */
255 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
256 POWER1_VW_OFF | POWER1_GVSS_ON | POWER1_VDD_ON);
257 mdelay(2);
258
259 /* COM SIGNAL ON (PICTL[3] = L) */
260 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, PICTRL_INIT_STATE);
261
262 /* COM ON, DAC ON, VCC5_ON */
263 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
264 POWER0_COM_DCLK | POWER0_COM_DOUT | POWER0_DAC_ON |
265 POWER0_COM_ON | POWER0_VCC5_ON);
266
267 /* VW ON, GVSS ON, VDD ON */
268 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
269 POWER1_VW_ON | POWER1_GVSS_ON | POWER1_VDD_ON);
270
271 /* Signals output enable */
272 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, data: 0);
273
274 /* Set Phase Adjust */
275 lcdtg_set_phadadj(lcd, mode: lcd->mode);
276
277 /* Initialize for Input Signals from ATI */
278 corgi_ssp_lcdtg_send(lcd, POLCTRL_ADRS,
279 POLCTRL_SYNC_POL_RISE | POLCTRL_EN_POL_RISE |
280 POLCTRL_DATA_POL_RISE | POLCTRL_SYNC_ACT_L |
281 POLCTRL_EN_ACT_H);
282 udelay(1000);
283
284 switch (lcd->mode) {
285 case CORGI_LCD_MODE_VGA:
286 corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_VGA);
287 break;
288 case CORGI_LCD_MODE_QVGA:
289 default:
290 corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_QVGA);
291 break;
292 }
293}
294
295static void corgi_lcd_power_off(struct corgi_lcd *lcd)
296{
297 /* 60Hz x 2 frame = 16.7msec x 2 = 33.4 msec */
298 msleep(msecs: 34);
299
300 /* (1)VW OFF */
301 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
302 POWER1_VW_OFF | POWER1_GVSS_ON | POWER1_VDD_ON);
303
304 /* (2)COM OFF */
305 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS, PICTRL_COM_SIGNAL_OFF);
306 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
307 POWER0_DAC_ON | POWER0_COM_OFF | POWER0_VCC5_ON);
308
309 /* (3)Set Common Voltage Bias 0V */
310 lcdtg_set_common_voltage(lcd, POWER0_DAC_ON | POWER0_COM_OFF |
311 POWER0_VCC5_ON, data: 0);
312
313 /* (4)GVSS OFF */
314 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
315 POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_ON);
316
317 /* (5)VCC5 OFF */
318 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
319 POWER0_DAC_ON | POWER0_COM_OFF | POWER0_VCC5_OFF);
320
321 /* (6)Set PDWN, INIOFF, DACOFF */
322 corgi_ssp_lcdtg_send(lcd, PICTRL_ADRS,
323 PICTRL_INIOFF | PICTRL_DAC_SIGNAL_OFF |
324 PICTRL_POWER_DOWN | PICTRL_COM_SIGNAL_OFF);
325
326 /* (7)DAC OFF */
327 corgi_ssp_lcdtg_send(lcd, POWERREG0_ADRS,
328 POWER0_DAC_OFF | POWER0_COM_OFF | POWER0_VCC5_OFF);
329
330 /* (8)VDD OFF */
331 corgi_ssp_lcdtg_send(lcd, POWERREG1_ADRS,
332 POWER1_VW_OFF | POWER1_GVSS_OFF | POWER1_VDD_OFF);
333}
334
335static int corgi_lcd_set_mode(struct lcd_device *ld, struct fb_videomode *m)
336{
337 struct corgi_lcd *lcd = lcd_get_data(ld_dev: ld);
338 int mode = CORGI_LCD_MODE_QVGA;
339
340 if (m->xres == 640 || m->xres == 480)
341 mode = CORGI_LCD_MODE_VGA;
342
343 if (lcd->mode == mode)
344 return 0;
345
346 lcdtg_set_phadadj(lcd, mode);
347
348 switch (mode) {
349 case CORGI_LCD_MODE_VGA:
350 corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_VGA);
351 break;
352 case CORGI_LCD_MODE_QVGA:
353 default:
354 corgi_ssp_lcdtg_send(lcd, RESCTL_ADRS, RESCTL_QVGA);
355 break;
356 }
357
358 lcd->mode = mode;
359 return 0;
360}
361
362static int corgi_lcd_set_power(struct lcd_device *ld, int power)
363{
364 struct corgi_lcd *lcd = lcd_get_data(ld_dev: ld);
365
366 if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
367 corgi_lcd_power_on(lcd);
368
369 if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
370 corgi_lcd_power_off(lcd);
371
372 lcd->power = power;
373 return 0;
374}
375
376static int corgi_lcd_get_power(struct lcd_device *ld)
377{
378 struct corgi_lcd *lcd = lcd_get_data(ld_dev: ld);
379
380 return lcd->power;
381}
382
383static struct lcd_ops corgi_lcd_ops = {
384 .get_power = corgi_lcd_get_power,
385 .set_power = corgi_lcd_set_power,
386 .set_mode = corgi_lcd_set_mode,
387};
388
389static int corgi_bl_get_intensity(struct backlight_device *bd)
390{
391 struct corgi_lcd *lcd = bl_get_data(bl_dev: bd);
392
393 return lcd->intensity;
394}
395
396static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity)
397{
398 int cont;
399
400 if (intensity > 0x10)
401 intensity += 0x10;
402
403 corgi_ssp_lcdtg_send(lcd, DUTYCTRL_ADRS, data: intensity);
404
405 /* Bit 5 via GPIO_BACKLIGHT_CONT */
406 cont = !!(intensity & 0x20);
407
408 if (lcd->backlight_cont)
409 gpiod_set_value_cansleep(desc: lcd->backlight_cont, value: cont);
410
411 if (lcd->backlight_on)
412 gpiod_set_value_cansleep(desc: lcd->backlight_on, value: intensity);
413
414 if (lcd->kick_battery)
415 lcd->kick_battery();
416
417 lcd->intensity = intensity;
418 return 0;
419}
420
421static int corgi_bl_update_status(struct backlight_device *bd)
422{
423 struct corgi_lcd *lcd = bl_get_data(bl_dev: bd);
424 int intensity = backlight_get_brightness(bd);
425
426 if (corgibl_flags & CORGIBL_SUSPENDED)
427 intensity = 0;
428
429 if ((corgibl_flags & CORGIBL_BATTLOW) && intensity > lcd->limit_mask)
430 intensity = lcd->limit_mask;
431
432 return corgi_bl_set_intensity(lcd, intensity);
433}
434
435void corgi_lcd_limit_intensity(int limit)
436{
437 if (limit)
438 corgibl_flags |= CORGIBL_BATTLOW;
439 else
440 corgibl_flags &= ~CORGIBL_BATTLOW;
441
442 backlight_update_status(bd: the_corgi_lcd->bl_dev);
443}
444EXPORT_SYMBOL(corgi_lcd_limit_intensity);
445
446static const struct backlight_ops corgi_bl_ops = {
447 .get_brightness = corgi_bl_get_intensity,
448 .update_status = corgi_bl_update_status,
449};
450
451#ifdef CONFIG_PM_SLEEP
452static int corgi_lcd_suspend(struct device *dev)
453{
454 struct corgi_lcd *lcd = dev_get_drvdata(dev);
455
456 corgibl_flags |= CORGIBL_SUSPENDED;
457 corgi_bl_set_intensity(lcd, intensity: 0);
458 corgi_lcd_set_power(ld: lcd->lcd_dev, power: FB_BLANK_POWERDOWN);
459 return 0;
460}
461
462static int corgi_lcd_resume(struct device *dev)
463{
464 struct corgi_lcd *lcd = dev_get_drvdata(dev);
465
466 corgibl_flags &= ~CORGIBL_SUSPENDED;
467 corgi_lcd_set_power(ld: lcd->lcd_dev, power: FB_BLANK_UNBLANK);
468 backlight_update_status(bd: lcd->bl_dev);
469 return 0;
470}
471#endif
472
473static SIMPLE_DEV_PM_OPS(corgi_lcd_pm_ops, corgi_lcd_suspend, corgi_lcd_resume);
474
475static int setup_gpio_backlight(struct corgi_lcd *lcd,
476 struct corgi_lcd_platform_data *pdata)
477{
478 struct spi_device *spi = lcd->spi_dev;
479
480 lcd->backlight_on = devm_gpiod_get_optional(dev: &spi->dev,
481 con_id: "BL_ON", flags: GPIOD_OUT_LOW);
482 if (IS_ERR(ptr: lcd->backlight_on))
483 return PTR_ERR(ptr: lcd->backlight_on);
484
485 lcd->backlight_cont = devm_gpiod_get_optional(dev: &spi->dev, con_id: "BL_CONT",
486 flags: GPIOD_OUT_LOW);
487 if (IS_ERR(ptr: lcd->backlight_cont))
488 return PTR_ERR(ptr: lcd->backlight_cont);
489
490 return 0;
491}
492
493static int corgi_lcd_probe(struct spi_device *spi)
494{
495 struct backlight_properties props;
496 struct corgi_lcd_platform_data *pdata = dev_get_platdata(dev: &spi->dev);
497 struct corgi_lcd *lcd;
498 int ret = 0;
499
500 if (pdata == NULL) {
501 dev_err(&spi->dev, "platform data not available\n");
502 return -EINVAL;
503 }
504
505 lcd = devm_kzalloc(dev: &spi->dev, size: sizeof(struct corgi_lcd), GFP_KERNEL);
506 if (!lcd)
507 return -ENOMEM;
508
509 lcd->spi_dev = spi;
510
511 lcd->lcd_dev = devm_lcd_device_register(dev: &spi->dev, name: "corgi_lcd",
512 parent: &spi->dev, devdata: lcd, ops: &corgi_lcd_ops);
513 if (IS_ERR(ptr: lcd->lcd_dev))
514 return PTR_ERR(ptr: lcd->lcd_dev);
515
516 lcd->power = FB_BLANK_POWERDOWN;
517 lcd->mode = (pdata) ? pdata->init_mode : CORGI_LCD_MODE_VGA;
518
519 memset(&props, 0, sizeof(struct backlight_properties));
520 props.type = BACKLIGHT_RAW;
521 props.max_brightness = pdata->max_intensity;
522 lcd->bl_dev = devm_backlight_device_register(dev: &spi->dev, name: "corgi_bl",
523 parent: &spi->dev, devdata: lcd, ops: &corgi_bl_ops,
524 props: &props);
525 if (IS_ERR(ptr: lcd->bl_dev))
526 return PTR_ERR(ptr: lcd->bl_dev);
527
528 lcd->bl_dev->props.brightness = pdata->default_intensity;
529 lcd->bl_dev->props.power = FB_BLANK_UNBLANK;
530
531 ret = setup_gpio_backlight(lcd, pdata);
532 if (ret)
533 return ret;
534
535 lcd->kick_battery = pdata->kick_battery;
536
537 spi_set_drvdata(spi, data: lcd);
538 corgi_lcd_set_power(ld: lcd->lcd_dev, power: FB_BLANK_UNBLANK);
539 backlight_update_status(bd: lcd->bl_dev);
540
541 lcd->limit_mask = pdata->limit_mask;
542 the_corgi_lcd = lcd;
543 return 0;
544}
545
546static void corgi_lcd_remove(struct spi_device *spi)
547{
548 struct corgi_lcd *lcd = spi_get_drvdata(spi);
549
550 lcd->bl_dev->props.power = FB_BLANK_UNBLANK;
551 lcd->bl_dev->props.brightness = 0;
552 backlight_update_status(bd: lcd->bl_dev);
553 corgi_lcd_set_power(ld: lcd->lcd_dev, power: FB_BLANK_POWERDOWN);
554}
555
556static struct spi_driver corgi_lcd_driver = {
557 .driver = {
558 .name = "corgi-lcd",
559 .pm = &corgi_lcd_pm_ops,
560 },
561 .probe = corgi_lcd_probe,
562 .remove = corgi_lcd_remove,
563};
564
565module_spi_driver(corgi_lcd_driver);
566
567MODULE_DESCRIPTION("LCD and backlight driver for SHARP C7x0/Cxx00");
568MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
569MODULE_LICENSE("GPL");
570MODULE_ALIAS("spi:corgi-lcd");
571

source code of linux/drivers/video/backlight/corgi_lcd.c