2 * Rockchip IO Voltage Domain driver
4 * Copyright 2014 MundoReader S.L.
5 * Copyright 2014 Google, Inc.
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/err.h>
20 #include <linux/mfd/syscon.h>
22 #include <linux/platform_device.h>
23 #include <linux/regmap.h>
24 #include <linux/regulator/consumer.h>
26 #define MAX_SUPPLIES 16
29 * The max voltage for 1.8V and 3.3V come from the Rockchip datasheet under
30 * "Recommended Operating Conditions" for "Digital GPIO". When the typical
31 * is 3.3V the max is 3.6V. When the typical is 1.8V the max is 1.98V.
33 * They are used like this:
34 * - If the voltage on a rail is above the "1.8" voltage (1.98V) we'll tell the
36 * - If the voltage on a rail is above the "3.3" voltage (3.6V) we'll consider
37 * that to be an error.
39 #define MAX_VOLTAGE_1_8 1980000
40 #define MAX_VOLTAGE_3_3 3600000
42 #define RK3288_SOC_CON2 0x24c
43 #define RK3288_SOC_CON2_FLASH0 BIT(7)
44 #define RK3288_SOC_FLASH_SUPPLY_NUM 2
46 #define RK3366_SOC_CON6 0x418
47 #define RK3366_SOC_CON6_FLASH0 BIT(14)
48 #define RK3366_SOC_FLASH_SUPPLY_NUM 2
50 #define RK3368_SOC_CON15 0x43c
51 #define RK3368_SOC_CON15_FLASH0 BIT(14)
52 #define RK3368_SOC_FLASH_SUPPLY_NUM 2
54 struct rockchip_iodomain;
57 * @supplies: voltage settings matching the register bits.
59 struct rockchip_iodomain_soc_data {
61 const char *supply_names[MAX_SUPPLIES];
62 void (*init)(struct rockchip_iodomain *iod);
65 struct rockchip_iodomain_supply {
66 struct rockchip_iodomain *iod;
67 struct regulator *reg;
68 struct notifier_block nb;
72 struct rockchip_iodomain {
75 struct rockchip_iodomain_soc_data *soc_data;
76 struct rockchip_iodomain_supply supplies[MAX_SUPPLIES];
79 static int rockchip_iodomain_write(struct rockchip_iodomain_supply *supply,
82 struct rockchip_iodomain *iod = supply->iod;
87 val = (uV > MAX_VOLTAGE_1_8) ? 0 : 1;
90 /* apply hiword-mask */
91 val |= (BIT(supply->idx) << 16);
93 ret = regmap_write(iod->grf, iod->soc_data->grf_offset, val);
95 dev_err(iod->dev, "Couldn't write to GRF\n");
100 static int rockchip_iodomain_notify(struct notifier_block *nb,
104 struct rockchip_iodomain_supply *supply =
105 container_of(nb, struct rockchip_iodomain_supply, nb);
110 * According to Rockchip it's important to keep the SoC IO domain
111 * higher than (or equal to) the external voltage. That means we need
112 * to change it before external voltage changes happen in the case
115 * Note that in the "pre" change we pick the max possible voltage that
116 * the regulator might end up at (the client requests a range and we
117 * don't know for certain the exact voltage). Right now we rely on the
118 * slop in MAX_VOLTAGE_1_8 and MAX_VOLTAGE_3_3 to save us if clients
119 * request something like a max of 3.6V when they really want 3.3V.
120 * We could attempt to come up with better rules if this fails.
122 if (event & REGULATOR_EVENT_PRE_VOLTAGE_CHANGE) {
123 struct pre_voltage_change_data *pvc_data = data;
125 uV = max_t(unsigned long, pvc_data->old_uV, pvc_data->max_uV);
126 } else if (event & (REGULATOR_EVENT_VOLTAGE_CHANGE |
127 REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE)) {
128 uV = (unsigned long)data;
133 dev_dbg(supply->iod->dev, "Setting to %d\n", uV);
135 if (uV > MAX_VOLTAGE_3_3) {
136 dev_err(supply->iod->dev, "Voltage too high: %d\n", uV);
138 if (event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
142 ret = rockchip_iodomain_write(supply, uV);
143 if (ret && event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
146 dev_info(supply->iod->dev, "Setting to %d done\n", uV);
150 static void rk3288_iodomain_init(struct rockchip_iodomain *iod)
155 /* if no flash supply we should leave things alone */
156 if (!iod->supplies[RK3288_SOC_FLASH_SUPPLY_NUM].reg)
160 * set flash0 iodomain to also use this framework
161 * instead of a special gpio.
163 val = RK3288_SOC_CON2_FLASH0 | (RK3288_SOC_CON2_FLASH0 << 16);
164 ret = regmap_write(iod->grf, RK3288_SOC_CON2, val);
166 dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
169 static void rk3366_iodomain_init(struct rockchip_iodomain *iod)
174 /* if no flash supply we should leave things alone */
175 if (!iod->supplies[RK3366_SOC_FLASH_SUPPLY_NUM].reg)
179 * set flash0 iodomain to also use this framework
180 * instead of a special gpio.
182 val = RK3366_SOC_CON6_FLASH0 | (RK3366_SOC_CON6_FLASH0 << 16);
183 ret = regmap_write(iod->grf, RK3368_SOC_CON15, val);
185 dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
188 static void rk3368_iodomain_init(struct rockchip_iodomain *iod)
193 /* if no flash supply we should leave things alone */
194 if (!iod->supplies[RK3368_SOC_FLASH_SUPPLY_NUM].reg)
198 * set flash0 iodomain to also use this framework
199 * instead of a special gpio.
201 val = RK3368_SOC_CON15_FLASH0 | (RK3368_SOC_CON15_FLASH0 << 16);
202 ret = regmap_write(iod->grf, RK3368_SOC_CON15, val);
204 dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
208 * On the rk3188 the io-domains are handled by a shared register with the
209 * lower 8 bits being still being continuing drive-strength settings.
211 static const struct rockchip_iodomain_soc_data soc_data_rk3188 = {
233 static const struct rockchip_iodomain_soc_data soc_data_rk3288 = {
236 "lcdc", /* LCDC_VDD */
237 "dvp", /* DVPIO_VDD */
238 "flash0", /* FLASH0_VDD (emmc) */
239 "flash1", /* FLASH1_VDD (sdio1) */
240 "wifi", /* APIO3_VDD (sdio0) */
241 "bb", /* APIO5_VDD */
242 "audio", /* APIO4_VDD */
243 "sdcard", /* SDMMC0_VDD (sdmmc) */
244 "gpio30", /* APIO1_VDD */
245 "gpio1830", /* APIO2_VDD */
247 .init = rk3288_iodomain_init,
250 static const struct rockchip_iodomain_soc_data soc_data_rk3366 = {
253 "lcdc", /* LCDC_IOVDD */
254 "dvpts", /* DVP_IOVDD */
255 "flash", /* FLASH_IOVDD (emmc) */
256 "wifibt", /* APIO1_IOVDD */
258 "audio", /* AUDIO_IODVDD */
259 "sdcard", /* SDMMC_IOVDD (sdmmc) */
260 "tphdsor", /* APIO2_IOVDD */
262 .init = rk3366_iodomain_init,
265 static const struct rockchip_iodomain_soc_data soc_data_rk3368 = {
269 "dvp", /* DVPIO_VDD */
270 "flash0", /* FLASH0_VDD (emmc) */
271 "wifi", /* APIO2_VDD (sdio0) */
273 "audio", /* APIO3_VDD */
274 "sdcard", /* SDMMC0_VDD (sdmmc) */
275 "gpio30", /* APIO1_VDD */
276 "gpio1830", /* APIO4_VDD (gpujtag) */
278 .init = rk3368_iodomain_init,
281 static const struct rockchip_iodomain_soc_data soc_data_rk3368_pmu = {
288 "pmu", /*PMU IO domain*/
289 "vop", /*LCDC IO domain*/
293 static const struct of_device_id rockchip_iodomain_match[] = {
295 .compatible = "rockchip,rk3188-io-voltage-domain",
296 .data = (void *)&soc_data_rk3188
299 .compatible = "rockchip,rk3288-io-voltage-domain",
300 .data = (void *)&soc_data_rk3288
303 .compatible = "rockchip,rk3366-io-voltage-domain",
304 .data = (void *)&soc_data_rk3366
307 .compatible = "rockchip,rk3368-io-voltage-domain",
308 .data = (void *)&soc_data_rk3368
311 .compatible = "rockchip,rk3368-pmu-io-voltage-domain",
312 .data = (void *)&soc_data_rk3368_pmu
316 MODULE_DEVICE_TABLE(of, rockchip_iodomain_match);
318 static int rockchip_iodomain_probe(struct platform_device *pdev)
320 struct device_node *np = pdev->dev.of_node;
321 const struct of_device_id *match;
322 struct rockchip_iodomain *iod;
328 iod = devm_kzalloc(&pdev->dev, sizeof(*iod), GFP_KERNEL);
332 iod->dev = &pdev->dev;
333 platform_set_drvdata(pdev, iod);
335 match = of_match_node(rockchip_iodomain_match, np);
336 iod->soc_data = (struct rockchip_iodomain_soc_data *)match->data;
338 iod->grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
339 if (IS_ERR(iod->grf)) {
340 dev_err(&pdev->dev, "couldn't find grf regmap\n");
341 return PTR_ERR(iod->grf);
344 for (i = 0; i < MAX_SUPPLIES; i++) {
345 const char *supply_name = iod->soc_data->supply_names[i];
346 struct rockchip_iodomain_supply *supply = &iod->supplies[i];
347 struct regulator *reg;
353 reg = devm_regulator_get_optional(iod->dev, supply_name);
357 /* If a supply wasn't specified, that's OK */
360 else if (ret != -EPROBE_DEFER)
361 dev_err(iod->dev, "couldn't get regulator %s\n",
366 /* set initial correct value */
367 uV = regulator_get_voltage(reg);
369 /* must be a regulator we can get the voltage of */
371 dev_err(iod->dev, "Can't determine voltage: %s\n",
376 if (uV > MAX_VOLTAGE_3_3) {
378 "%d uV is too high. May damage SoC!\n",
384 /* setup our supply */
388 supply->nb.notifier_call = rockchip_iodomain_notify;
390 ret = rockchip_iodomain_write(supply, uV);
396 /* register regulator notifier */
397 ret = regulator_register_notifier(reg, &supply->nb);
400 "regulator notifier request failed\n");
406 if (iod->soc_data->init)
407 iod->soc_data->init(iod);
412 for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
413 struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
416 regulator_unregister_notifier(io_supply->reg,
423 static int rockchip_iodomain_remove(struct platform_device *pdev)
425 struct rockchip_iodomain *iod = platform_get_drvdata(pdev);
428 for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
429 struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
432 regulator_unregister_notifier(io_supply->reg,
439 static struct platform_driver rockchip_iodomain_driver = {
440 .probe = rockchip_iodomain_probe,
441 .remove = rockchip_iodomain_remove,
443 .name = "rockchip-iodomain",
444 .of_match_table = rockchip_iodomain_match,
448 module_platform_driver(rockchip_iodomain_driver);
450 MODULE_DESCRIPTION("Rockchip IO-domain driver");
451 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
452 MODULE_AUTHOR("Doug Anderson <dianders@chromium.org>");
453 MODULE_LICENSE("GPL v2");