1 // SPDX-License-Identifier: GPL-2.0
2 /* Author: Dan Scally <djrscally@gmail.com> */
3
4 #include <linux/acpi.h>
5 #include <linux/clkdev.h>
6 #include <linux/clk-provider.h>
7 #include <linux/device.h>
8 #include <linux/gpio/consumer.h>
9 #include <linux/regulator/driver.h>
10 #include <linux/slab.h>
11
12 #include "common.h"
13
14 /*
15 * The regulators have to have .ops to be valid, but the only ops we actually
16 * support are .enable and .disable which are handled via .ena_gpiod. Pass an
17 * empty struct to clear the check without lying about capabilities.
18 */
19 static const struct regulator_ops int3472_gpio_regulator_ops;
20
skl_int3472_clk_prepare(struct clk_hw * hw)21 static int skl_int3472_clk_prepare(struct clk_hw *hw)
22 {
23 struct int3472_gpio_clock *clk = to_int3472_clk(hw);
24
25 gpiod_set_value_cansleep(clk->ena_gpio, 1);
26 return 0;
27 }
28
skl_int3472_clk_unprepare(struct clk_hw * hw)29 static void skl_int3472_clk_unprepare(struct clk_hw *hw)
30 {
31 struct int3472_gpio_clock *clk = to_int3472_clk(hw);
32
33 gpiod_set_value_cansleep(clk->ena_gpio, 0);
34 }
35
skl_int3472_clk_enable(struct clk_hw * hw)36 static int skl_int3472_clk_enable(struct clk_hw *hw)
37 {
38 /*
39 * We're just turning a GPIO on to enable the clock, which operation
40 * has the potential to sleep. Given .enable() cannot sleep, but
41 * .prepare() can, we toggle the GPIO in .prepare() instead. Thus,
42 * nothing to do here.
43 */
44 return 0;
45 }
46
skl_int3472_clk_disable(struct clk_hw * hw)47 static void skl_int3472_clk_disable(struct clk_hw *hw)
48 {
49 /* Likewise, nothing to do here... */
50 }
51
skl_int3472_get_clk_frequency(struct int3472_discrete_device * int3472)52 static unsigned int skl_int3472_get_clk_frequency(struct int3472_discrete_device *int3472)
53 {
54 union acpi_object *obj;
55 unsigned int freq;
56
57 obj = skl_int3472_get_acpi_buffer(int3472->sensor, "SSDB");
58 if (IS_ERR(obj))
59 return 0; /* report rate as 0 on error */
60
61 if (obj->buffer.length < CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET + sizeof(u32)) {
62 dev_err(int3472->dev, "The buffer is too small\n");
63 kfree(obj);
64 return 0;
65 }
66
67 freq = *(u32 *)(obj->buffer.pointer + CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET);
68
69 kfree(obj);
70 return freq;
71 }
72
skl_int3472_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)73 static unsigned long skl_int3472_clk_recalc_rate(struct clk_hw *hw,
74 unsigned long parent_rate)
75 {
76 struct int3472_gpio_clock *clk = to_int3472_clk(hw);
77
78 return clk->frequency;
79 }
80
81 static const struct clk_ops skl_int3472_clock_ops = {
82 .prepare = skl_int3472_clk_prepare,
83 .unprepare = skl_int3472_clk_unprepare,
84 .enable = skl_int3472_clk_enable,
85 .disable = skl_int3472_clk_disable,
86 .recalc_rate = skl_int3472_clk_recalc_rate,
87 };
88
skl_int3472_register_clock(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,u32 polarity)89 int skl_int3472_register_clock(struct int3472_discrete_device *int3472,
90 struct acpi_resource_gpio *agpio, u32 polarity)
91 {
92 char *path = agpio->resource_source.string_ptr;
93 struct clk_init_data init = {
94 .ops = &skl_int3472_clock_ops,
95 .flags = CLK_GET_RATE_NOCACHE,
96 };
97 int ret;
98
99 if (int3472->clock.cl)
100 return -EBUSY;
101
102 int3472->clock.ena_gpio = acpi_get_and_request_gpiod(path, agpio->pin_table[0],
103 "int3472,clk-enable");
104 if (IS_ERR(int3472->clock.ena_gpio))
105 return dev_err_probe(int3472->dev, PTR_ERR(int3472->clock.ena_gpio),
106 "getting clk-enable GPIO\n");
107
108 if (polarity == GPIO_ACTIVE_LOW)
109 gpiod_toggle_active_low(int3472->clock.ena_gpio);
110
111 /* Ensure the pin is in output mode and non-active state */
112 gpiod_direction_output(int3472->clock.ena_gpio, 0);
113
114 init.name = kasprintf(GFP_KERNEL, "%s-clk",
115 acpi_dev_name(int3472->adev));
116 if (!init.name) {
117 ret = -ENOMEM;
118 goto out_put_gpio;
119 }
120
121 int3472->clock.frequency = skl_int3472_get_clk_frequency(int3472);
122
123 int3472->clock.clk_hw.init = &init;
124 int3472->clock.clk = clk_register(&int3472->adev->dev,
125 &int3472->clock.clk_hw);
126 if (IS_ERR(int3472->clock.clk)) {
127 ret = PTR_ERR(int3472->clock.clk);
128 goto out_free_init_name;
129 }
130
131 int3472->clock.cl = clkdev_create(int3472->clock.clk, NULL,
132 int3472->sensor_name);
133 if (!int3472->clock.cl) {
134 ret = -ENOMEM;
135 goto err_unregister_clk;
136 }
137
138 kfree(init.name);
139 return 0;
140
141 err_unregister_clk:
142 clk_unregister(int3472->clock.clk);
143 out_free_init_name:
144 kfree(init.name);
145 out_put_gpio:
146 gpiod_put(int3472->clock.ena_gpio);
147
148 return ret;
149 }
150
skl_int3472_unregister_clock(struct int3472_discrete_device * int3472)151 void skl_int3472_unregister_clock(struct int3472_discrete_device *int3472)
152 {
153 if (!int3472->clock.cl)
154 return;
155
156 clkdev_drop(int3472->clock.cl);
157 clk_unregister(int3472->clock.clk);
158 gpiod_put(int3472->clock.ena_gpio);
159 }
160
skl_int3472_register_regulator(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio)161 int skl_int3472_register_regulator(struct int3472_discrete_device *int3472,
162 struct acpi_resource_gpio *agpio)
163 {
164 const struct int3472_sensor_config *sensor_config;
165 char *path = agpio->resource_source.string_ptr;
166 struct regulator_consumer_supply supply_map;
167 struct regulator_init_data init_data = { };
168 struct regulator_config cfg = { };
169 int ret;
170
171 sensor_config = int3472->sensor_config;
172 if (IS_ERR(sensor_config)) {
173 dev_err(int3472->dev, "No sensor module config\n");
174 return PTR_ERR(sensor_config);
175 }
176
177 if (!sensor_config->supply_map.supply) {
178 dev_err(int3472->dev, "No supply name defined\n");
179 return -ENODEV;
180 }
181
182 init_data.constraints.valid_ops_mask = REGULATOR_CHANGE_STATUS;
183 init_data.num_consumer_supplies = 1;
184 supply_map = sensor_config->supply_map;
185 supply_map.dev_name = int3472->sensor_name;
186 init_data.consumer_supplies = &supply_map;
187
188 snprintf(int3472->regulator.regulator_name,
189 sizeof(int3472->regulator.regulator_name), "%s-regulator",
190 acpi_dev_name(int3472->adev));
191 snprintf(int3472->regulator.supply_name,
192 GPIO_REGULATOR_SUPPLY_NAME_LENGTH, "supply-0");
193
194 int3472->regulator.rdesc = INT3472_REGULATOR(
195 int3472->regulator.regulator_name,
196 int3472->regulator.supply_name,
197 &int3472_gpio_regulator_ops);
198
199 int3472->regulator.gpio = acpi_get_and_request_gpiod(path, agpio->pin_table[0],
200 "int3472,regulator");
201 if (IS_ERR(int3472->regulator.gpio)) {
202 dev_err(int3472->dev, "Failed to get regulator GPIO line\n");
203 return PTR_ERR(int3472->regulator.gpio);
204 }
205
206 /* Ensure the pin is in output mode and non-active state */
207 gpiod_direction_output(int3472->regulator.gpio, 0);
208
209 cfg.dev = &int3472->adev->dev;
210 cfg.init_data = &init_data;
211 cfg.ena_gpiod = int3472->regulator.gpio;
212
213 int3472->regulator.rdev = regulator_register(int3472->dev,
214 &int3472->regulator.rdesc,
215 &cfg);
216 if (IS_ERR(int3472->regulator.rdev)) {
217 ret = PTR_ERR(int3472->regulator.rdev);
218 goto err_free_gpio;
219 }
220
221 return 0;
222
223 err_free_gpio:
224 gpiod_put(int3472->regulator.gpio);
225
226 return ret;
227 }
228
skl_int3472_unregister_regulator(struct int3472_discrete_device * int3472)229 void skl_int3472_unregister_regulator(struct int3472_discrete_device *int3472)
230 {
231 regulator_unregister(int3472->regulator.rdev);
232 gpiod_put(int3472->regulator.gpio);
233 }
234