1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PFSM (Pre-configurable Finite State Machine) driver for TI TPS65224/TPS6594/TPS6593/LP8764 PMICs
4 *
5 * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/
6 */
7
8 #include <linux/errno.h>
9 #include <linux/fs.h>
10 #include <linux/interrupt.h>
11 #include <linux/ioctl.h>
12 #include <linux/miscdevice.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
16
17 #include <linux/mfd/tps6594.h>
18
19 #include <linux/tps6594_pfsm.h>
20
21 #define TPS6594_STARTUP_DEST_MCU_ONLY_VAL 2
22 #define TPS6594_STARTUP_DEST_ACTIVE_VAL 3
23 #define TPS6594_STARTUP_DEST_SHIFT 5
24 #define TPS6594_STARTUP_DEST_MCU_ONLY (TPS6594_STARTUP_DEST_MCU_ONLY_VAL \
25 << TPS6594_STARTUP_DEST_SHIFT)
26 #define TPS6594_STARTUP_DEST_ACTIVE (TPS6594_STARTUP_DEST_ACTIVE_VAL \
27 << TPS6594_STARTUP_DEST_SHIFT)
28
29 /*
30 * To update the PMIC firmware, the user must be able to access
31 * page 0 (user registers) and page 1 (NVM control and configuration).
32 */
33 #define TPS6594_PMIC_MAX_POS 0x200
34
35 #define TPS6594_FILE_TO_PFSM(f) container_of((f)->private_data, struct tps6594_pfsm, miscdev)
36
37 /**
38 * struct tps6594_pfsm - device private data structure
39 *
40 * @miscdev: misc device infos
41 * @regmap: regmap for accessing the device registers
42 * @chip_id: chip identifier of the device
43 */
44 struct tps6594_pfsm {
45 struct miscdevice miscdev;
46 struct regmap *regmap;
47 unsigned long chip_id;
48 };
49
tps6594_pfsm_read(struct file * f,char __user * buf,size_t count,loff_t * ppos)50 static ssize_t tps6594_pfsm_read(struct file *f, char __user *buf,
51 size_t count, loff_t *ppos)
52 {
53 struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f);
54 loff_t pos = *ppos;
55 unsigned int val;
56 int ret;
57 int i;
58
59 if (pos < 0)
60 return -EINVAL;
61 if (pos >= TPS6594_PMIC_MAX_POS)
62 return 0;
63 if (count > TPS6594_PMIC_MAX_POS - pos)
64 count = TPS6594_PMIC_MAX_POS - pos;
65
66 for (i = 0 ; i < count ; i++) {
67 ret = regmap_read(pfsm->regmap, pos + i, &val);
68 if (ret)
69 return ret;
70
71 if (put_user(val, buf + i))
72 return -EFAULT;
73 }
74
75 *ppos = pos + count;
76
77 return count;
78 }
79
tps6594_pfsm_write(struct file * f,const char __user * buf,size_t count,loff_t * ppos)80 static ssize_t tps6594_pfsm_write(struct file *f, const char __user *buf,
81 size_t count, loff_t *ppos)
82 {
83 struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f);
84 loff_t pos = *ppos;
85 char val;
86 int ret;
87 int i;
88
89 if (pos < 0)
90 return -EINVAL;
91 if (pos >= TPS6594_PMIC_MAX_POS || !count)
92 return 0;
93 if (count > TPS6594_PMIC_MAX_POS - pos)
94 count = TPS6594_PMIC_MAX_POS - pos;
95
96 for (i = 0 ; i < count ; i++) {
97 if (get_user(val, buf + i))
98 return -EFAULT;
99
100 ret = regmap_write(pfsm->regmap, pos + i, val);
101 if (ret)
102 return ret;
103 }
104
105 *ppos = pos + count;
106
107 return count;
108 }
109
tps6594_pfsm_configure_ret_trig(struct regmap * regmap,u8 gpio_ret,u8 ddr_ret)110 static int tps6594_pfsm_configure_ret_trig(struct regmap *regmap, u8 gpio_ret, u8 ddr_ret)
111 {
112 int ret;
113
114 if (gpio_ret)
115 ret = regmap_set_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
116 TPS6594_BIT_TRIGGER_I2C(5) | TPS6594_BIT_TRIGGER_I2C(6));
117 else
118 ret = regmap_clear_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
119 TPS6594_BIT_TRIGGER_I2C(5) | TPS6594_BIT_TRIGGER_I2C(6));
120 if (ret)
121 return ret;
122
123 if (ddr_ret)
124 ret = regmap_set_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
125 TPS6594_BIT_TRIGGER_I2C(7));
126 else
127 ret = regmap_clear_bits(regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
128 TPS6594_BIT_TRIGGER_I2C(7));
129
130 return ret;
131 }
132
tps6594_pfsm_ioctl(struct file * f,unsigned int cmd,unsigned long arg)133 static long tps6594_pfsm_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
134 {
135 struct tps6594_pfsm *pfsm = TPS6594_FILE_TO_PFSM(f);
136 struct pmic_state_opt state_opt;
137 void __user *argp = (void __user *)arg;
138 unsigned int regmap_reg, mask;
139 int ret = -ENOIOCTLCMD;
140
141 switch (cmd) {
142 case PMIC_GOTO_STANDBY:
143 /* Disable LP mode on TPS6594 Family PMIC */
144 if (pfsm->chip_id != TPS65224) {
145 ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2,
146 TPS6594_BIT_LP_STANDBY_SEL);
147
148 if (ret)
149 return ret;
150 }
151
152 /* Force trigger */
153 ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
154 TPS6594_BIT_TRIGGER_I2C(0), TPS6594_BIT_TRIGGER_I2C(0));
155 break;
156 case PMIC_GOTO_LP_STANDBY:
157 /* TPS65224 does not support LP STANDBY */
158 if (pfsm->chip_id == TPS65224)
159 return ret;
160
161 /* Enable LP mode */
162 ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_RTC_CTRL_2,
163 TPS6594_BIT_LP_STANDBY_SEL);
164 if (ret)
165 return ret;
166
167 /* Force trigger */
168 ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
169 TPS6594_BIT_TRIGGER_I2C(0), TPS6594_BIT_TRIGGER_I2C(0));
170 break;
171 case PMIC_UPDATE_PGM:
172 /* Force trigger */
173 ret = regmap_write_bits(pfsm->regmap, TPS6594_REG_FSM_I2C_TRIGGERS,
174 TPS6594_BIT_TRIGGER_I2C(3), TPS6594_BIT_TRIGGER_I2C(3));
175 break;
176 case PMIC_SET_ACTIVE_STATE:
177 /* Modify NSLEEP1-2 bits */
178 ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS,
179 TPS6594_BIT_NSLEEP1B | TPS6594_BIT_NSLEEP2B);
180 break;
181 case PMIC_SET_MCU_ONLY_STATE:
182 /* TPS65224 does not support MCU_ONLY_STATE */
183 if (pfsm->chip_id == TPS65224)
184 return ret;
185
186 if (copy_from_user(&state_opt, argp, sizeof(state_opt)))
187 return -EFAULT;
188
189 /* Configure retention triggers */
190 ret = tps6594_pfsm_configure_ret_trig(pfsm->regmap, state_opt.gpio_retention,
191 state_opt.ddr_retention);
192 if (ret)
193 return ret;
194
195 /* Modify NSLEEP1-2 bits */
196 ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS,
197 TPS6594_BIT_NSLEEP1B);
198 if (ret)
199 return ret;
200
201 ret = regmap_set_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS,
202 TPS6594_BIT_NSLEEP2B);
203 break;
204 case PMIC_SET_RETENTION_STATE:
205 if (copy_from_user(&state_opt, argp, sizeof(state_opt)))
206 return -EFAULT;
207
208 /* Configure wake-up destination */
209 if (pfsm->chip_id == TPS65224) {
210 regmap_reg = TPS65224_REG_STARTUP_CTRL;
211 mask = TPS65224_MASK_STARTUP_DEST;
212 } else {
213 regmap_reg = TPS6594_REG_RTC_CTRL_2;
214 mask = TPS6594_MASK_STARTUP_DEST;
215 }
216
217 if (state_opt.mcu_only_startup_dest)
218 ret = regmap_write_bits(pfsm->regmap, regmap_reg,
219 mask, TPS6594_STARTUP_DEST_MCU_ONLY);
220 else
221 ret = regmap_write_bits(pfsm->regmap, regmap_reg,
222 mask, TPS6594_STARTUP_DEST_ACTIVE);
223 if (ret)
224 return ret;
225
226 /* Configure retention triggers */
227 ret = tps6594_pfsm_configure_ret_trig(pfsm->regmap, state_opt.gpio_retention,
228 state_opt.ddr_retention);
229 if (ret)
230 return ret;
231
232 /* Modify NSLEEP1-2 bits */
233 ret = regmap_clear_bits(pfsm->regmap, TPS6594_REG_FSM_NSLEEP_TRIGGERS,
234 pfsm->chip_id == TPS65224 ?
235 TPS6594_BIT_NSLEEP1B : TPS6594_BIT_NSLEEP2B);
236 break;
237 }
238
239 return ret;
240 }
241
242 static const struct file_operations tps6594_pfsm_fops = {
243 .owner = THIS_MODULE,
244 .llseek = generic_file_llseek,
245 .read = tps6594_pfsm_read,
246 .write = tps6594_pfsm_write,
247 .unlocked_ioctl = tps6594_pfsm_ioctl,
248 .compat_ioctl = compat_ptr_ioctl,
249 };
250
tps6594_pfsm_isr(int irq,void * dev_id)251 static irqreturn_t tps6594_pfsm_isr(int irq, void *dev_id)
252 {
253 struct platform_device *pdev = dev_id;
254 int i;
255
256 for (i = 0 ; i < pdev->num_resources ; i++) {
257 if (irq == platform_get_irq_byname(pdev, pdev->resource[i].name)) {
258 dev_err(pdev->dev.parent, "%s event detected\n", pdev->resource[i].name);
259 return IRQ_HANDLED;
260 }
261 }
262
263 return IRQ_NONE;
264 }
265
tps6594_pfsm_probe(struct platform_device * pdev)266 static int tps6594_pfsm_probe(struct platform_device *pdev)
267 {
268 struct tps6594_pfsm *pfsm;
269 struct tps6594 *tps = dev_get_drvdata(pdev->dev.parent);
270 struct device *dev = &pdev->dev;
271 int irq;
272 int ret;
273 int i;
274
275 pfsm = devm_kzalloc(dev, sizeof(struct tps6594_pfsm), GFP_KERNEL);
276 if (!pfsm)
277 return -ENOMEM;
278
279 pfsm->regmap = tps->regmap;
280
281 pfsm->miscdev.minor = MISC_DYNAMIC_MINOR;
282 pfsm->miscdev.name = devm_kasprintf(dev, GFP_KERNEL, "pfsm-%ld-0x%02x",
283 tps->chip_id, tps->reg);
284 pfsm->miscdev.fops = &tps6594_pfsm_fops;
285 pfsm->miscdev.parent = dev->parent;
286 pfsm->chip_id = tps->chip_id;
287
288 for (i = 0 ; i < pdev->num_resources ; i++) {
289 irq = platform_get_irq_byname(pdev, pdev->resource[i].name);
290 if (irq < 0)
291 return irq;
292
293 ret = devm_request_threaded_irq(dev, irq, NULL,
294 tps6594_pfsm_isr, IRQF_ONESHOT,
295 pdev->resource[i].name, pdev);
296 if (ret)
297 return dev_err_probe(dev, ret, "Failed to request irq\n");
298 }
299
300 platform_set_drvdata(pdev, pfsm);
301
302 return misc_register(&pfsm->miscdev);
303 }
304
tps6594_pfsm_remove(struct platform_device * pdev)305 static void tps6594_pfsm_remove(struct platform_device *pdev)
306 {
307 struct tps6594_pfsm *pfsm = platform_get_drvdata(pdev);
308
309 misc_deregister(&pfsm->miscdev);
310 }
311
312 static struct platform_driver tps6594_pfsm_driver = {
313 .driver = {
314 .name = "tps6594-pfsm",
315 },
316 .probe = tps6594_pfsm_probe,
317 .remove_new = tps6594_pfsm_remove,
318 };
319
320 module_platform_driver(tps6594_pfsm_driver);
321
322 MODULE_ALIAS("platform:tps6594-pfsm");
323 MODULE_AUTHOR("Julien Panis <jpanis@baylibre.com>");
324 MODULE_DESCRIPTION("TPS6594 Pre-configurable Finite State Machine Driver");
325 MODULE_LICENSE("GPL");
326