Merge tag 'drm-intel-gt-next-2023-12-15' of git://anongit.freedesktop.org/drm/drm...
[linux-block.git] / drivers / leds / leds-pca955x.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
4  *
5  * Author: Nate Case <ncase@xes-inc.com>
6  *
7  * LED driver for various PCA955x I2C LED drivers
8  *
9  * Supported devices:
10  *
11  *      Device          Description             7-bit slave address
12  *      ------          -----------             -------------------
13  *      PCA9550         2-bit driver            0x60 .. 0x61
14  *      PCA9551         8-bit driver            0x60 .. 0x67
15  *      PCA9552         16-bit driver           0x60 .. 0x67
16  *      PCA9553/01      4-bit driver            0x62
17  *      PCA9553/02      4-bit driver            0x63
18  *
19  * Philips PCA955x LED driver chips follow a register map as shown below:
20  *
21  *      Control Register                Description
22  *      ----------------                -----------
23  *      0x0                             Input register 0
24  *                                      ..
25  *      NUM_INPUT_REGS - 1              Last Input register X
26  *
27  *      NUM_INPUT_REGS                  Frequency prescaler 0
28  *      NUM_INPUT_REGS + 1              PWM register 0
29  *      NUM_INPUT_REGS + 2              Frequency prescaler 1
30  *      NUM_INPUT_REGS + 3              PWM register 1
31  *
32  *      NUM_INPUT_REGS + 4              LED selector 0
33  *      NUM_INPUT_REGS + 4
34  *          + NUM_LED_REGS - 1          Last LED selector
35  *
36  *  where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
37  *  bits the chip supports.
38  */
39
40 #include <linux/bitops.h>
41 #include <linux/ctype.h>
42 #include <linux/delay.h>
43 #include <linux/err.h>
44 #include <linux/gpio/driver.h>
45 #include <linux/i2c.h>
46 #include <linux/leds.h>
47 #include <linux/module.h>
48 #include <linux/of.h>
49 #include <linux/property.h>
50 #include <linux/slab.h>
51 #include <linux/string.h>
52
53 #include <dt-bindings/leds/leds-pca955x.h>
54
55 /* LED select registers determine the source that drives LED outputs */
56 #define PCA955X_LS_LED_ON       0x0     /* Output LOW */
57 #define PCA955X_LS_LED_OFF      0x1     /* Output HI-Z */
58 #define PCA955X_LS_BLINK0       0x2     /* Blink at PWM0 rate */
59 #define PCA955X_LS_BLINK1       0x3     /* Blink at PWM1 rate */
60
61 #define PCA955X_GPIO_INPUT      LED_OFF
62 #define PCA955X_GPIO_HIGH       LED_OFF
63 #define PCA955X_GPIO_LOW        LED_FULL
64
65 enum pca955x_type {
66         pca9550,
67         pca9551,
68         pca9552,
69         ibm_pca9552,
70         pca9553,
71 };
72
73 struct pca955x_chipdef {
74         int                     bits;
75         u8                      slv_addr;       /* 7-bit slave address mask */
76         int                     slv_addr_shift; /* Number of bits to ignore */
77 };
78
79 static const struct pca955x_chipdef pca955x_chipdefs[] = {
80         [pca9550] = {
81                 .bits           = 2,
82                 .slv_addr       = /* 110000x */ 0x60,
83                 .slv_addr_shift = 1,
84         },
85         [pca9551] = {
86                 .bits           = 8,
87                 .slv_addr       = /* 1100xxx */ 0x60,
88                 .slv_addr_shift = 3,
89         },
90         [pca9552] = {
91                 .bits           = 16,
92                 .slv_addr       = /* 1100xxx */ 0x60,
93                 .slv_addr_shift = 3,
94         },
95         [ibm_pca9552] = {
96                 .bits           = 16,
97                 .slv_addr       = /* 0110xxx */ 0x30,
98                 .slv_addr_shift = 3,
99         },
100         [pca9553] = {
101                 .bits           = 4,
102                 .slv_addr       = /* 110001x */ 0x62,
103                 .slv_addr_shift = 1,
104         },
105 };
106
107 struct pca955x {
108         struct mutex lock;
109         struct pca955x_led *leds;
110         const struct pca955x_chipdef    *chipdef;
111         struct i2c_client       *client;
112         unsigned long active_pins;
113 #ifdef CONFIG_LEDS_PCA955X_GPIO
114         struct gpio_chip gpio;
115 #endif
116 };
117
118 struct pca955x_led {
119         struct pca955x  *pca955x;
120         struct led_classdev     led_cdev;
121         int                     led_num;        /* 0 .. 15 potentially */
122         u32                     type;
123         enum led_default_state  default_state;
124         struct fwnode_handle    *fwnode;
125 };
126
127 struct pca955x_platform_data {
128         struct pca955x_led      *leds;
129         int                     num_leds;
130 };
131
132 /* 8 bits per input register */
133 static inline int pca95xx_num_input_regs(int bits)
134 {
135         return (bits + 7) / 8;
136 }
137
138 /*
139  * Return an LED selector register value based on an existing one, with
140  * the appropriate 2-bit state value set for the given LED number (0-3).
141  */
142 static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
143 {
144         return (oldval & (~(0x3 << (led_num << 1)))) |
145                 ((state & 0x3) << (led_num << 1));
146 }
147
148 /*
149  * Write to frequency prescaler register, used to program the
150  * period of the PWM output.  period = (PSCx + 1) / 38
151  */
152 static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
153 {
154         struct pca955x *pca955x = i2c_get_clientdata(client);
155         u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + (2 * n);
156         int ret;
157
158         ret = i2c_smbus_write_byte_data(client, cmd, val);
159         if (ret < 0)
160                 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
161                         __func__, n, val, ret);
162         return ret;
163 }
164
165 /*
166  * Write to PWM register, which determines the duty cycle of the
167  * output.  LED is OFF when the count is less than the value of this
168  * register, and ON when it is greater.  If PWMx == 0, LED is always OFF.
169  *
170  * Duty cycle is (256 - PWMx) / 256
171  */
172 static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
173 {
174         struct pca955x *pca955x = i2c_get_clientdata(client);
175         u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
176         int ret;
177
178         ret = i2c_smbus_write_byte_data(client, cmd, val);
179         if (ret < 0)
180                 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
181                         __func__, n, val, ret);
182         return ret;
183 }
184
185 /*
186  * Write to LED selector register, which determines the source that
187  * drives the LED output.
188  */
189 static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
190 {
191         struct pca955x *pca955x = i2c_get_clientdata(client);
192         u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
193         int ret;
194
195         ret = i2c_smbus_write_byte_data(client, cmd, val);
196         if (ret < 0)
197                 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
198                         __func__, n, val, ret);
199         return ret;
200 }
201
202 /*
203  * Read the LED selector register, which determines the source that
204  * drives the LED output.
205  */
206 static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val)
207 {
208         struct pca955x *pca955x = i2c_get_clientdata(client);
209         u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n;
210         int ret;
211
212         ret = i2c_smbus_read_byte_data(client, cmd);
213         if (ret < 0) {
214                 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
215                         __func__, n, ret);
216                 return ret;
217         }
218         *val = (u8)ret;
219         return 0;
220 }
221
222 static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val)
223 {
224         struct pca955x *pca955x = i2c_get_clientdata(client);
225         u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);
226         int ret;
227
228         ret = i2c_smbus_read_byte_data(client, cmd);
229         if (ret < 0) {
230                 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
231                         __func__, n, ret);
232                 return ret;
233         }
234         *val = (u8)ret;
235         return 0;
236 }
237
238 static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)
239 {
240         struct pca955x_led *pca955x_led = container_of(led_cdev,
241                                                        struct pca955x_led,
242                                                        led_cdev);
243         struct pca955x *pca955x = pca955x_led->pca955x;
244         u8 ls, pwm;
245         int ret;
246
247         ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls);
248         if (ret)
249                 return ret;
250
251         ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3;
252         switch (ls) {
253         case PCA955X_LS_LED_ON:
254                 ret = LED_FULL;
255                 break;
256         case PCA955X_LS_LED_OFF:
257                 ret = LED_OFF;
258                 break;
259         case PCA955X_LS_BLINK0:
260                 ret = LED_HALF;
261                 break;
262         case PCA955X_LS_BLINK1:
263                 ret = pca955x_read_pwm(pca955x->client, 1, &pwm);
264                 if (ret)
265                         return ret;
266                 ret = 255 - pwm;
267                 break;
268         }
269
270         return ret;
271 }
272
273 static int pca955x_led_set(struct led_classdev *led_cdev,
274                             enum led_brightness value)
275 {
276         struct pca955x_led *pca955x_led;
277         struct pca955x *pca955x;
278         u8 ls;
279         int chip_ls;    /* which LSx to use (0-3 potentially) */
280         int ls_led;     /* which set of bits within LSx to use (0-3) */
281         int ret;
282
283         pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
284         pca955x = pca955x_led->pca955x;
285
286         chip_ls = pca955x_led->led_num / 4;
287         ls_led = pca955x_led->led_num % 4;
288
289         mutex_lock(&pca955x->lock);
290
291         ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
292         if (ret)
293                 goto out;
294
295         switch (value) {
296         case LED_FULL:
297                 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
298                 break;
299         case LED_OFF:
300                 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
301                 break;
302         case LED_HALF:
303                 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
304                 break;
305         default:
306                 /*
307                  * Use PWM1 for all other values.  This has the unwanted
308                  * side effect of making all LEDs on the chip share the
309                  * same brightness level if set to a value other than
310                  * OFF, HALF, or FULL.  But, this is probably better than
311                  * just turning off for all other values.
312                  */
313                 ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
314                 if (ret)
315                         goto out;
316                 ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
317                 break;
318         }
319
320         ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
321
322 out:
323         mutex_unlock(&pca955x->lock);
324
325         return ret;
326 }
327
328 #ifdef CONFIG_LEDS_PCA955X_GPIO
329 /*
330  * Read the INPUT register, which contains the state of LEDs.
331  */
332 static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
333 {
334         int ret = i2c_smbus_read_byte_data(client, n);
335
336         if (ret < 0) {
337                 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
338                         __func__, n, ret);
339                 return ret;
340         }
341         *val = (u8)ret;
342         return 0;
343
344 }
345
346 static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
347 {
348         struct pca955x *pca955x = gpiochip_get_data(gc);
349
350         return test_and_set_bit(offset, &pca955x->active_pins) ? -EBUSY : 0;
351 }
352
353 static void pca955x_gpio_free_pin(struct gpio_chip *gc, unsigned int offset)
354 {
355         struct pca955x *pca955x = gpiochip_get_data(gc);
356
357         clear_bit(offset, &pca955x->active_pins);
358 }
359
360 static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
361                              int val)
362 {
363         struct pca955x *pca955x = gpiochip_get_data(gc);
364         struct pca955x_led *led = &pca955x->leds[offset];
365
366         if (val)
367                 return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_HIGH);
368
369         return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_LOW);
370 }
371
372 static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
373                                    int val)
374 {
375         pca955x_set_value(gc, offset, val);
376 }
377
378 static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
379 {
380         struct pca955x *pca955x = gpiochip_get_data(gc);
381         struct pca955x_led *led = &pca955x->leds[offset];
382         u8 reg = 0;
383
384         /* There is nothing we can do about errors */
385         pca955x_read_input(pca955x->client, led->led_num / 8, &reg);
386
387         return !!(reg & (1 << (led->led_num % 8)));
388 }
389
390 static int pca955x_gpio_direction_input(struct gpio_chip *gc,
391                                         unsigned int offset)
392 {
393         struct pca955x *pca955x = gpiochip_get_data(gc);
394         struct pca955x_led *led = &pca955x->leds[offset];
395
396         /* To use as input ensure pin is not driven. */
397         return pca955x_led_set(&led->led_cdev, PCA955X_GPIO_INPUT);
398 }
399
400 static int pca955x_gpio_direction_output(struct gpio_chip *gc,
401                                          unsigned int offset, int val)
402 {
403         return pca955x_set_value(gc, offset, val);
404 }
405 #endif /* CONFIG_LEDS_PCA955X_GPIO */
406
407 static struct pca955x_platform_data *
408 pca955x_get_pdata(struct i2c_client *client, const struct pca955x_chipdef *chip)
409 {
410         struct pca955x_platform_data *pdata;
411         struct pca955x_led *led;
412         struct fwnode_handle *child;
413         int count;
414
415         count = device_get_child_node_count(&client->dev);
416         if (count > chip->bits)
417                 return ERR_PTR(-ENODEV);
418
419         pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
420         if (!pdata)
421                 return ERR_PTR(-ENOMEM);
422
423         pdata->leds = devm_kcalloc(&client->dev,
424                                    chip->bits, sizeof(struct pca955x_led),
425                                    GFP_KERNEL);
426         if (!pdata->leds)
427                 return ERR_PTR(-ENOMEM);
428
429         device_for_each_child_node(&client->dev, child) {
430                 u32 reg;
431                 int res;
432
433                 res = fwnode_property_read_u32(child, "reg", &reg);
434                 if ((res != 0) || (reg >= chip->bits))
435                         continue;
436
437                 led = &pdata->leds[reg];
438                 led->type = PCA955X_TYPE_LED;
439                 led->fwnode = child;
440                 led->default_state = led_init_default_state_get(child);
441
442                 fwnode_property_read_u32(child, "type", &led->type);
443         }
444
445         pdata->num_leds = chip->bits;
446
447         return pdata;
448 }
449
450 static int pca955x_probe(struct i2c_client *client)
451 {
452         struct pca955x *pca955x;
453         struct pca955x_led *pca955x_led;
454         const struct pca955x_chipdef *chip;
455         struct led_classdev *led;
456         struct led_init_data init_data;
457         struct i2c_adapter *adapter;
458         int i, err;
459         struct pca955x_platform_data *pdata;
460         bool set_default_label = false;
461         bool keep_pwm = false;
462         char default_label[8];
463
464         chip = i2c_get_match_data(client);
465         if (!chip)
466                 return dev_err_probe(&client->dev, -ENODEV, "unknown chip\n");
467
468         adapter = client->adapter;
469         pdata = dev_get_platdata(&client->dev);
470         if (!pdata) {
471                 pdata = pca955x_get_pdata(client, chip);
472                 if (IS_ERR(pdata))
473                         return PTR_ERR(pdata);
474         }
475
476         /* Make sure the slave address / chip type combo given is possible */
477         if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
478             chip->slv_addr) {
479                 dev_err(&client->dev, "invalid slave address %02x\n",
480                         client->addr);
481                 return -ENODEV;
482         }
483
484         dev_info(&client->dev, "leds-pca955x: Using %s %d-bit LED driver at "
485                  "slave address 0x%02x\n", client->name, chip->bits,
486                  client->addr);
487
488         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
489                 return -EIO;
490
491         if (pdata->num_leds != chip->bits) {
492                 dev_err(&client->dev,
493                         "board info claims %d LEDs on a %d-bit chip\n",
494                         pdata->num_leds, chip->bits);
495                 return -ENODEV;
496         }
497
498         pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
499         if (!pca955x)
500                 return -ENOMEM;
501
502         pca955x->leds = devm_kcalloc(&client->dev, chip->bits,
503                                      sizeof(*pca955x_led), GFP_KERNEL);
504         if (!pca955x->leds)
505                 return -ENOMEM;
506
507         i2c_set_clientdata(client, pca955x);
508
509         mutex_init(&pca955x->lock);
510         pca955x->client = client;
511         pca955x->chipdef = chip;
512
513         init_data.devname_mandatory = false;
514         init_data.devicename = "pca955x";
515
516         for (i = 0; i < chip->bits; i++) {
517                 pca955x_led = &pca955x->leds[i];
518                 pca955x_led->led_num = i;
519                 pca955x_led->pca955x = pca955x;
520                 pca955x_led->type = pdata->leds[i].type;
521
522                 switch (pca955x_led->type) {
523                 case PCA955X_TYPE_NONE:
524                 case PCA955X_TYPE_GPIO:
525                         break;
526                 case PCA955X_TYPE_LED:
527                         led = &pca955x_led->led_cdev;
528                         led->brightness_set_blocking = pca955x_led_set;
529                         led->brightness_get = pca955x_led_get;
530
531                         if (pdata->leds[i].default_state == LEDS_DEFSTATE_OFF) {
532                                 err = pca955x_led_set(led, LED_OFF);
533                                 if (err)
534                                         return err;
535                         } else if (pdata->leds[i].default_state == LEDS_DEFSTATE_ON) {
536                                 err = pca955x_led_set(led, LED_FULL);
537                                 if (err)
538                                         return err;
539                         }
540
541                         init_data.fwnode = pdata->leds[i].fwnode;
542
543                         if (is_of_node(init_data.fwnode)) {
544                                 if (to_of_node(init_data.fwnode)->name[0] ==
545                                     '\0')
546                                         set_default_label = true;
547                                 else
548                                         set_default_label = false;
549                         } else {
550                                 set_default_label = true;
551                         }
552
553                         if (set_default_label) {
554                                 snprintf(default_label, sizeof(default_label),
555                                          "%d", i);
556                                 init_data.default_label = default_label;
557                         } else {
558                                 init_data.default_label = NULL;
559                         }
560
561                         err = devm_led_classdev_register_ext(&client->dev, led,
562                                                              &init_data);
563                         if (err)
564                                 return err;
565
566                         set_bit(i, &pca955x->active_pins);
567
568                         /*
569                          * For default-state == "keep", let the core update the
570                          * brightness from the hardware, then check the
571                          * brightness to see if it's using PWM1. If so, PWM1
572                          * should not be written below.
573                          */
574                         if (pdata->leds[i].default_state == LEDS_DEFSTATE_KEEP) {
575                                 if (led->brightness != LED_FULL &&
576                                     led->brightness != LED_OFF &&
577                                     led->brightness != LED_HALF)
578                                         keep_pwm = true;
579                         }
580                 }
581         }
582
583         /* PWM0 is used for half brightness or 50% duty cycle */
584         err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
585         if (err)
586                 return err;
587
588         if (!keep_pwm) {
589                 /* PWM1 is used for variable brightness, default to OFF */
590                 err = pca955x_write_pwm(client, 1, 0);
591                 if (err)
592                         return err;
593         }
594
595         /* Set to fast frequency so we do not see flashing */
596         err = pca955x_write_psc(client, 0, 0);
597         if (err)
598                 return err;
599         err = pca955x_write_psc(client, 1, 0);
600         if (err)
601                 return err;
602
603 #ifdef CONFIG_LEDS_PCA955X_GPIO
604         pca955x->gpio.label = "gpio-pca955x";
605         pca955x->gpio.direction_input = pca955x_gpio_direction_input;
606         pca955x->gpio.direction_output = pca955x_gpio_direction_output;
607         pca955x->gpio.set = pca955x_gpio_set_value;
608         pca955x->gpio.get = pca955x_gpio_get_value;
609         pca955x->gpio.request = pca955x_gpio_request_pin;
610         pca955x->gpio.free = pca955x_gpio_free_pin;
611         pca955x->gpio.can_sleep = 1;
612         pca955x->gpio.base = -1;
613         pca955x->gpio.ngpio = chip->bits;
614         pca955x->gpio.parent = &client->dev;
615         pca955x->gpio.owner = THIS_MODULE;
616
617         err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
618                                      pca955x);
619         if (err) {
620                 /* Use data->gpio.dev as a flag for freeing gpiochip */
621                 pca955x->gpio.parent = NULL;
622                 dev_warn(&client->dev, "could not add gpiochip\n");
623                 return err;
624         }
625         dev_info(&client->dev, "gpios %i...%i\n",
626                  pca955x->gpio.base, pca955x->gpio.base +
627                  pca955x->gpio.ngpio - 1);
628 #endif
629
630         return 0;
631 }
632
633 static const struct i2c_device_id pca955x_id[] = {
634         { "pca9550", (kernel_ulong_t)&pca955x_chipdefs[pca9550] },
635         { "pca9551", (kernel_ulong_t)&pca955x_chipdefs[pca9551] },
636         { "pca9552", (kernel_ulong_t)&pca955x_chipdefs[pca9552] },
637         { "ibm-pca9552", (kernel_ulong_t)&pca955x_chipdefs[ibm_pca9552] },
638         { "pca9553", (kernel_ulong_t)&pca955x_chipdefs[pca9553] },
639         {}
640 };
641 MODULE_DEVICE_TABLE(i2c, pca955x_id);
642
643 static const struct of_device_id of_pca955x_match[] = {
644         { .compatible = "nxp,pca9550", .data = &pca955x_chipdefs[pca9550] },
645         { .compatible = "nxp,pca9551", .data = &pca955x_chipdefs[pca9551] },
646         { .compatible = "nxp,pca9552", .data = &pca955x_chipdefs[pca9552] },
647         { .compatible = "ibm,pca9552", .data = &pca955x_chipdefs[ibm_pca9552] },
648         { .compatible = "nxp,pca9553", .data = &pca955x_chipdefs[pca9553] },
649         {}
650 };
651 MODULE_DEVICE_TABLE(of, of_pca955x_match);
652
653 static struct i2c_driver pca955x_driver = {
654         .driver = {
655                 .name   = "leds-pca955x",
656                 .of_match_table = of_pca955x_match,
657         },
658         .probe = pca955x_probe,
659         .id_table = pca955x_id,
660 };
661
662 module_i2c_driver(pca955x_driver);
663
664 MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
665 MODULE_DESCRIPTION("PCA955x LED driver");
666 MODULE_LICENSE("GPL v2");