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 RK3368_GRF_SOC_CON15 0x43c
47 #define RK3368_GRF_SOC_CON15_FLASH0 BIT(14)
48 #define RK3368_SOC_FLASH_SUPPLY_NUM 2
51 struct rockchip_iodomain;
54 * @supplies: voltage settings matching the register bits.
56 struct rockchip_iodomain_soc_data {
58 const char *supply_names[MAX_SUPPLIES];
59 void (*init)(struct rockchip_iodomain *iod);
62 struct rockchip_iodomain_supply {
63 struct rockchip_iodomain *iod;
64 struct regulator *reg;
65 struct notifier_block nb;
69 struct rockchip_iodomain {
72 struct rockchip_iodomain_soc_data *soc_data;
73 struct rockchip_iodomain_supply supplies[MAX_SUPPLIES];
76 static int rockchip_iodomain_write(struct rockchip_iodomain_supply *supply,
79 struct rockchip_iodomain *iod = supply->iod;
84 val = (uV > MAX_VOLTAGE_1_8) ? 0 : 1;
87 /* apply hiword-mask */
88 val |= (BIT(supply->idx) << 16);
90 ret = regmap_write(iod->grf, iod->soc_data->grf_offset, val);
92 dev_err(iod->dev, "Couldn't write to GRF\n");
97 static int rockchip_iodomain_notify(struct notifier_block *nb,
101 struct rockchip_iodomain_supply *supply =
102 container_of(nb, struct rockchip_iodomain_supply, nb);
107 * According to Rockchip it's important to keep the SoC IO domain
108 * higher than (or equal to) the external voltage. That means we need
109 * to change it before external voltage changes happen in the case
112 * Note that in the "pre" change we pick the max possible voltage that
113 * the regulator might end up at (the client requests a range and we
114 * don't know for certain the exact voltage). Right now we rely on the
115 * slop in MAX_VOLTAGE_1_8 and MAX_VOLTAGE_3_3 to save us if clients
116 * request something like a max of 3.6V when they really want 3.3V.
117 * We could attempt to come up with better rules if this fails.
120 if (event & REGULATOR_EVENT_PRE_VOLTAGE_CHANGE) {
121 struct pre_voltage_change_data *pvc_data = data;
123 uV = max_t(unsigned long, pvc_data->old_uV, pvc_data->max_uV);
126 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);
144 if (ret && event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
148 dev_info(supply->iod->dev, "Setting to %d done\n", uV);
152 static void rk3288_iodomain_init(struct rockchip_iodomain *iod)
157 /* if no flash supply we should leave things alone */
158 if (!iod->supplies[RK3288_SOC_FLASH_SUPPLY_NUM].reg)
162 * set flash0 iodomain to also use this framework
163 * instead of a special gpio.
165 val = RK3288_SOC_CON2_FLASH0 | (RK3288_SOC_CON2_FLASH0 << 16);
166 ret = regmap_write(iod->grf, RK3288_SOC_CON2, val);
168 dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
171 static void rk3368_iodomain_init(struct rockchip_iodomain *iod)
176 /* if no flash supply we should leave things alone */
177 if (!iod->supplies[RK3368_SOC_FLASH_SUPPLY_NUM].reg)
181 * set flash0 iodomain to also use this framework
182 * instead of a special gpio.
184 val = RK3368_GRF_SOC_CON15_FLASH0 | (RK3368_GRF_SOC_CON15_FLASH0 << 16);
185 ret = regmap_write(iod->grf, RK3368_GRF_SOC_CON15, val);
187 dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
192 * On the rk3188 the io-domains are handled by a shared register with the
193 * lower 8 bits being still being continuing drive-strength settings.
195 static const struct rockchip_iodomain_soc_data soc_data_rk3188 = {
217 static const struct rockchip_iodomain_soc_data soc_data_rk3288 = {
220 "lcdc", /* LCDC_VDD */
221 "dvp", /* DVPIO_VDD */
222 "flash0", /* FLASH0_VDD (emmc) */
223 "flash1", /* FLASH1_VDD (sdio1) */
224 "wifi", /* APIO3_VDD (sdio0) */
225 "bb", /* APIO5_VDD */
226 "audio", /* APIO4_VDD */
227 "sdcard", /* SDMMC0_VDD (sdmmc) */
228 "gpio30", /* APIO1_VDD */
229 "gpio1830", /* APIO2_VDD */
231 .init = rk3288_iodomain_init,
234 static const struct rockchip_iodomain_soc_data soc_data_rk3368 = {
238 "dvp_v18sel", /*DVP IO domain*/
239 "flash0_v18sel", /*FLASH0 IO domain*/
240 "wifi_v18sel", /*WIFI IO domain*/
242 "audio_v18sel", /*AUDIO IO domain*/
243 "sdcard_v18sel", /*SDCARD IO domain*/
244 "gpio30_v18sel", /*GPIO30 IO domain*/
245 "gpio1830_v18sel", /*GPIO1830 IO domain*/
247 .init = rk3368_iodomain_init,
251 static const struct of_device_id rockchip_iodomain_match[] = {
253 .compatible = "rockchip,rk3188-io-voltage-domain",
254 .data = (void *)&soc_data_rk3188
257 .compatible = "rockchip,rk3288-io-voltage-domain",
258 .data = (void *)&soc_data_rk3288
261 .compatible = "rockchip,rk3368-io-voltage-domain",
262 .data = (void *)&soc_data_rk3368
267 static int rockchip_iodomain_probe(struct platform_device *pdev)
269 struct device_node *np = pdev->dev.of_node;
270 const struct of_device_id *match;
271 struct rockchip_iodomain *iod;
277 iod = devm_kzalloc(&pdev->dev, sizeof(*iod), GFP_KERNEL);
281 iod->dev = &pdev->dev;
282 platform_set_drvdata(pdev, iod);
284 match = of_match_node(rockchip_iodomain_match, np);
285 iod->soc_data = (struct rockchip_iodomain_soc_data *)match->data;
287 iod->grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
288 if (IS_ERR(iod->grf)) {
289 dev_err(&pdev->dev, "couldn't find grf regmap\n");
290 return PTR_ERR(iod->grf);
293 for (i = 0; i < MAX_SUPPLIES; i++) {
294 const char *supply_name = iod->soc_data->supply_names[i];
295 struct rockchip_iodomain_supply *supply = &iod->supplies[i];
296 struct regulator *reg;
298 const char *regulator_name = NULL;
303 of_property_read_string(np, supply_name, ®ulator_name);
307 reg = regulator_get(NULL, regulator_name);
311 /* If a supply wasn't specified, that's OK */
314 else if (ret != -EPROBE_DEFER)
315 dev_err(iod->dev, "couldn't get regulator %s\n",
320 /* set initial correct value */
321 uV = regulator_get_voltage(reg);
323 /* must be a regulator we can get the voltage of */
325 dev_err(iod->dev, "Can't determine voltage: %s\n",
330 if (uV > MAX_VOLTAGE_3_3) {
332 "%d uV is too high. May damage SoC!\n",
338 /* setup our supply */
342 supply->nb.notifier_call = rockchip_iodomain_notify;
344 ret = rockchip_iodomain_write(supply, uV);
350 /* register regulator notifier */
351 ret = regulator_register_notifier(reg, &supply->nb);
354 "regulator notifier request failed\n");
360 if (iod->soc_data->init)
361 iod->soc_data->init(iod);
366 for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
367 struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
370 regulator_unregister_notifier(io_supply->reg,
377 static int rockchip_iodomain_remove(struct platform_device *pdev)
379 struct rockchip_iodomain *iod = platform_get_drvdata(pdev);
382 for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
383 struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
386 regulator_unregister_notifier(io_supply->reg,
393 static struct platform_driver rockchip_iodomain_driver = {
394 .probe = rockchip_iodomain_probe,
395 .remove = rockchip_iodomain_remove,
397 .name = "rockchip-iodomain",
398 .of_match_table = rockchip_iodomain_match,
402 module_platform_driver(rockchip_iodomain_driver);
404 MODULE_DESCRIPTION("Rockchip IO-domain driver");
405 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
406 MODULE_AUTHOR("Doug Anderson <dianders@chromium.org>");
407 MODULE_LICENSE("GPL v2");