2 * Dove thermal sensor driver
4 * Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch>
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
16 #include <linux/device.h>
17 #include <linux/err.h>
19 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/thermal.h>
25 #define DOVE_THERMAL_TEMP_OFFSET 1
26 #define DOVE_THERMAL_TEMP_MASK 0x1FF
28 /* Dove Thermal Manager Control and Status Register */
29 #define PMU_TM_DISABLE_OFFS 0
30 #define PMU_TM_DISABLE_MASK (0x1 << PMU_TM_DISABLE_OFFS)
32 /* Dove Theraml Diode Control 0 Register */
33 #define PMU_TDC0_SW_RST_MASK (0x1 << 1)
34 #define PMU_TDC0_SEL_VCAL_OFFS 5
35 #define PMU_TDC0_SEL_VCAL_MASK (0x3 << PMU_TDC0_SEL_VCAL_OFFS)
36 #define PMU_TDC0_REF_CAL_CNT_OFFS 11
37 #define PMU_TDC0_REF_CAL_CNT_MASK (0x1FF << PMU_TDC0_REF_CAL_CNT_OFFS)
38 #define PMU_TDC0_AVG_NUM_OFFS 25
39 #define PMU_TDC0_AVG_NUM_MASK (0x7 << PMU_TDC0_AVG_NUM_OFFS)
41 /* Dove Thermal Diode Control 1 Register */
42 #define PMU_TEMP_DIOD_CTRL1_REG 0x04
43 #define PMU_TDC1_TEMP_VALID_MASK (0x1 << 10)
45 /* Dove Thermal Sensor Dev Structure */
46 struct dove_thermal_priv
{
48 void __iomem
*control
;
51 static int dove_init_sensor(const struct dove_thermal_priv
*priv
)
56 /* Configure the Diode Control Register #0 */
57 reg
= readl_relaxed(priv
->control
);
59 /* Use average of 2 */
60 reg
&= ~PMU_TDC0_AVG_NUM_MASK
;
61 reg
|= (0x1 << PMU_TDC0_AVG_NUM_OFFS
);
63 /* Reference calibration value */
64 reg
&= ~PMU_TDC0_REF_CAL_CNT_MASK
;
65 reg
|= (0x0F1 << PMU_TDC0_REF_CAL_CNT_OFFS
);
67 /* Set the high level reference for calibration */
68 reg
&= ~PMU_TDC0_SEL_VCAL_MASK
;
69 reg
|= (0x2 << PMU_TDC0_SEL_VCAL_OFFS
);
70 writel(reg
, priv
->control
);
72 /* Reset the sensor */
73 reg
= readl_relaxed(priv
->control
);
74 writel((reg
| PMU_TDC0_SW_RST_MASK
), priv
->control
);
75 writel(reg
, priv
->control
);
77 /* Enable the sensor */
78 reg
= readl_relaxed(priv
->sensor
);
79 reg
&= ~PMU_TM_DISABLE_MASK
;
80 writel(reg
, priv
->sensor
);
82 /* Poll the sensor for the first reading */
83 for (i
= 0; i
< 1000000; i
++) {
84 reg
= readl_relaxed(priv
->sensor
);
85 if (reg
& DOVE_THERMAL_TEMP_MASK
)
95 static int dove_get_temp(struct thermal_zone_device
*thermal
,
99 struct dove_thermal_priv
*priv
= thermal
->devdata
;
102 reg
= readl_relaxed(priv
->control
+ PMU_TEMP_DIOD_CTRL1_REG
);
103 if ((reg
& PMU_TDC1_TEMP_VALID_MASK
) == 0x0) {
104 dev_err(&thermal
->device
,
105 "Temperature sensor reading not valid\n");
110 * Calculate temperature. See Section 8.10.1 of 88AP510,
111 * Documentation/arm/Marvell/README
113 reg
= readl_relaxed(priv
->sensor
);
114 reg
= (reg
>> DOVE_THERMAL_TEMP_OFFSET
) & DOVE_THERMAL_TEMP_MASK
;
115 *temp
= ((2281638UL - (7298*reg
)) / 10);
120 static struct thermal_zone_device_ops ops
= {
121 .get_temp
= dove_get_temp
,
124 static const struct of_device_id dove_thermal_id_table
[] = {
125 { .compatible
= "marvell,dove-thermal" },
129 static int dove_thermal_probe(struct platform_device
*pdev
)
131 struct thermal_zone_device
*thermal
= NULL
;
132 struct dove_thermal_priv
*priv
;
133 struct resource
*res
;
136 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
138 dev_err(&pdev
->dev
, "Failed to get platform resource\n");
142 priv
= devm_kzalloc(&pdev
->dev
, sizeof(*priv
), GFP_KERNEL
);
146 priv
->sensor
= devm_request_and_ioremap(&pdev
->dev
, res
);
148 dev_err(&pdev
->dev
, "Failed to request_ioremap memory\n");
149 return -EADDRNOTAVAIL
;
152 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 1);
154 dev_err(&pdev
->dev
, "Failed to get platform resource\n");
157 priv
->control
= devm_request_and_ioremap(&pdev
->dev
, res
);
158 if (!priv
->control
) {
159 dev_err(&pdev
->dev
, "Failed to request_ioremap memory\n");
160 return -EADDRNOTAVAIL
;
163 ret
= dove_init_sensor(priv
);
165 dev_err(&pdev
->dev
, "Failed to initialize sensor\n");
169 thermal
= thermal_zone_device_register("dove_thermal", 0, 0,
170 priv
, &ops
, NULL
, 0, 0);
171 if (IS_ERR(thermal
)) {
173 "Failed to register thermal zone device\n");
174 return PTR_ERR(thermal
);
177 platform_set_drvdata(pdev
, thermal
);
182 static int dove_thermal_exit(struct platform_device
*pdev
)
184 struct thermal_zone_device
*dove_thermal
=
185 platform_get_drvdata(pdev
);
187 thermal_zone_device_unregister(dove_thermal
);
188 platform_set_drvdata(pdev
, NULL
);
193 MODULE_DEVICE_TABLE(of
, dove_thermal_id_table
);
195 static struct platform_driver dove_thermal_driver
= {
196 .probe
= dove_thermal_probe
,
197 .remove
= dove_thermal_exit
,
199 .name
= "dove_thermal",
200 .owner
= THIS_MODULE
,
201 .of_match_table
= of_match_ptr(dove_thermal_id_table
),
205 module_platform_driver(dove_thermal_driver
);
207 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
208 MODULE_DESCRIPTION("Dove thermal driver");
209 MODULE_LICENSE("GPL");