linux/drivers/thermal/k3_bandgap.c
Uwe Kleine-König ff96e615ea thermal: k3_bandgap: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-09-29 12:34:17 +02:00

266 lines
8.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* TI Bandgap temperature sensor driver for K3 SoC Family
*
* Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/thermal.h>
#include <linux/types.h>
#include "thermal_hwmon.h"
#define K3_VTM_DEVINFO_PWR0_OFFSET 0x4
#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK 0xf0
#define K3_VTM_TMPSENS0_CTRL_OFFSET 0x80
#define K3_VTM_REGS_PER_TS 0x10
#define K3_VTM_TS_STAT_DTEMP_MASK 0x3ff
#define K3_VTM_TMPSENS_CTRL_CBIASSEL BIT(0)
#define K3_VTM_TMPSENS_CTRL_SOC BIT(5)
#define K3_VTM_TMPSENS_CTRL_CLRZ BIT(6)
#define K3_VTM_TMPSENS_CTRL_CLKON_REQ BIT(7)
#define K3_VTM_ADC_BEGIN_VAL 540
#define K3_VTM_ADC_END_VAL 944
static const int k3_adc_to_temp[] = {
-40000, -40000, -40000, -40000, -39800, -39400, -39000, -38600, -38200,
-37800, -37400, -37000, -36600, -36200, -35800, -35300, -34700, -34200,
-33800, -33400, -33000, -32600, -32200, -31800, -31400, -31000, -30600,
-30200, -29800, -29400, -29000, -28600, -28200, -27700, -27100, -26600,
-26200, -25800, -25400, -25000, -24600, -24200, -23800, -23400, -23000,
-22600, -22200, -21800, -21400, -21000, -20500, -19900, -19400, -19000,
-18600, -18200, -17800, -17400, -17000, -16600, -16200, -15800, -15400,
-15000, -14600, -14200, -13800, -13400, -13000, -12500, -11900, -11400,
-11000, -10600, -10200, -9800, -9400, -9000, -8600, -8200, -7800, -7400,
-7000, -6600, -6200, -5800, -5400, -5000, -4500, -3900, -3400, -3000,
-2600, -2200, -1800, -1400, -1000, -600, -200, 200, 600, 1000, 1400,
1800, 2200, 2600, 3000, 3400, 3900, 4500, 5000, 5400, 5800, 6200, 6600,
7000, 7400, 7800, 8200, 8600, 9000, 9400, 9800, 10200, 10600, 11000,
11400, 11800, 12200, 12700, 13300, 13800, 14200, 14600, 15000, 15400,
15800, 16200, 16600, 17000, 17400, 17800, 18200, 18600, 19000, 19400,
19800, 20200, 20600, 21000, 21400, 21900, 22500, 23000, 23400, 23800,
24200, 24600, 25000, 25400, 25800, 26200, 26600, 27000, 27400, 27800,
28200, 28600, 29000, 29400, 29800, 30200, 30600, 31000, 31400, 31900,
32500, 33000, 33400, 33800, 34200, 34600, 35000, 35400, 35800, 36200,
36600, 37000, 37400, 37800, 38200, 38600, 39000, 39400, 39800, 40200,
40600, 41000, 41400, 41800, 42200, 42600, 43100, 43700, 44200, 44600,
45000, 45400, 45800, 46200, 46600, 47000, 47400, 47800, 48200, 48600,
49000, 49400, 49800, 50200, 50600, 51000, 51400, 51800, 52200, 52600,
53000, 53400, 53800, 54200, 54600, 55000, 55400, 55900, 56500, 57000,
57400, 57800, 58200, 58600, 59000, 59400, 59800, 60200, 60600, 61000,
61400, 61800, 62200, 62600, 63000, 63400, 63800, 64200, 64600, 65000,
65400, 65800, 66200, 66600, 67000, 67400, 67800, 68200, 68600, 69000,
69400, 69800, 70200, 70600, 71000, 71500, 72100, 72600, 73000, 73400,
73800, 74200, 74600, 75000, 75400, 75800, 76200, 76600, 77000, 77400,
77800, 78200, 78600, 79000, 79400, 79800, 80200, 80600, 81000, 81400,
81800, 82200, 82600, 83000, 83400, 83800, 84200, 84600, 85000, 85400,
85800, 86200, 86600, 87000, 87400, 87800, 88200, 88600, 89000, 89400,
89800, 90200, 90600, 91000, 91400, 91800, 92200, 92600, 93000, 93400,
93800, 94200, 94600, 95000, 95400, 95800, 96200, 96600, 97000, 97500,
98100, 98600, 99000, 99400, 99800, 100200, 100600, 101000, 101400,
101800, 102200, 102600, 103000, 103400, 103800, 104200, 104600, 105000,
105400, 105800, 106200, 106600, 107000, 107400, 107800, 108200, 108600,
109000, 109400, 109800, 110200, 110600, 111000, 111400, 111800, 112200,
112600, 113000, 113400, 113800, 114200, 114600, 115000, 115400, 115800,
116200, 116600, 117000, 117400, 117800, 118200, 118600, 119000, 119400,
119800, 120200, 120600, 121000, 121400, 121800, 122200, 122600, 123000,
123400, 123800, 124200, 124600, 124900, 125000,
};
struct k3_bandgap {
void __iomem *base;
const struct k3_bandgap_data *conf;
};
/* common data structures */
struct k3_thermal_data {
struct thermal_zone_device *tzd;
struct k3_bandgap *bgp;
int sensor_id;
u32 ctrl_offset;
u32 stat_offset;
};
static unsigned int vtm_get_best_value(unsigned int s0, unsigned int s1,
unsigned int s2)
{
int d01 = abs(s0 - s1);
int d02 = abs(s0 - s2);
int d12 = abs(s1 - s2);
if (d01 <= d02 && d01 <= d12)
return (s0 + s1) / 2;
if (d02 <= d01 && d02 <= d12)
return (s0 + s2) / 2;
return (s1 + s2) / 2;
}
static int k3_bgp_read_temp(struct k3_thermal_data *devdata,
int *temp)
{
struct k3_bandgap *bgp;
unsigned int dtemp, s0, s1, s2;
bgp = devdata->bgp;
/*
* Errata is applicable for am654 pg 1.0 silicon. There
* is a variation of the order for 8-10 degree centigrade.
* Work around that by getting the average of two closest
* readings out of three readings everytime we want to
* report temperatures.
*
* Errata workaround.
*/
s0 = readl(bgp->base + devdata->stat_offset) &
K3_VTM_TS_STAT_DTEMP_MASK;
s1 = readl(bgp->base + devdata->stat_offset) &
K3_VTM_TS_STAT_DTEMP_MASK;
s2 = readl(bgp->base + devdata->stat_offset) &
K3_VTM_TS_STAT_DTEMP_MASK;
dtemp = vtm_get_best_value(s0, s1, s2);
if (dtemp < K3_VTM_ADC_BEGIN_VAL || dtemp > K3_VTM_ADC_END_VAL)
return -EINVAL;
*temp = k3_adc_to_temp[dtemp - K3_VTM_ADC_BEGIN_VAL];
return 0;
}
static int k3_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
{
struct k3_thermal_data *data = thermal_zone_device_priv(tz);
int ret = 0;
ret = k3_bgp_read_temp(data, temp);
if (ret)
return ret;
return ret;
}
static const struct thermal_zone_device_ops k3_of_thermal_ops = {
.get_temp = k3_thermal_get_temp,
};
static const struct of_device_id of_k3_bandgap_match[];
static int k3_bandgap_probe(struct platform_device *pdev)
{
int ret = 0, cnt, val, id;
struct resource *res;
struct device *dev = &pdev->dev;
struct k3_bandgap *bgp;
struct k3_thermal_data *data;
if (ARRAY_SIZE(k3_adc_to_temp) != (K3_VTM_ADC_END_VAL + 1 -
K3_VTM_ADC_BEGIN_VAL))
return -EINVAL;
bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
if (!bgp)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
bgp->base = devm_ioremap_resource(dev, res);
if (IS_ERR(bgp->base))
return PTR_ERR(bgp->base);
pm_runtime_enable(dev);
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
return ret;
}
/* Get the sensor count in the VTM */
val = readl(bgp->base + K3_VTM_DEVINFO_PWR0_OFFSET);
cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK;
cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK);
data = devm_kcalloc(dev, cnt, sizeof(*data), GFP_KERNEL);
if (!data) {
ret = -ENOMEM;
goto err_alloc;
}
/* Register the thermal sensors */
for (id = 0; id < cnt; id++) {
data[id].sensor_id = id;
data[id].bgp = bgp;
data[id].ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET +
id * K3_VTM_REGS_PER_TS;
data[id].stat_offset = data[id].ctrl_offset + 0x8;
val = readl(data[id].bgp->base + data[id].ctrl_offset);
val |= (K3_VTM_TMPSENS_CTRL_SOC |
K3_VTM_TMPSENS_CTRL_CLRZ |
K3_VTM_TMPSENS_CTRL_CLKON_REQ);
val &= ~K3_VTM_TMPSENS_CTRL_CBIASSEL;
writel(val, data[id].bgp->base + data[id].ctrl_offset);
data[id].tzd =
devm_thermal_of_zone_register(dev, id,
&data[id],
&k3_of_thermal_ops);
if (IS_ERR(data[id].tzd)) {
dev_err(dev, "thermal zone device is NULL\n");
ret = PTR_ERR(data[id].tzd);
goto err_alloc;
}
devm_thermal_add_hwmon_sysfs(dev, data[id].tzd);
}
return 0;
err_alloc:
pm_runtime_put_sync(dev);
pm_runtime_disable(dev);
return ret;
}
static void k3_bandgap_remove(struct platform_device *pdev)
{
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
}
static const struct of_device_id of_k3_bandgap_match[] = {
{
.compatible = "ti,am654-vtm",
},
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, of_k3_bandgap_match);
static struct platform_driver k3_bandgap_sensor_driver = {
.probe = k3_bandgap_probe,
.remove_new = k3_bandgap_remove,
.driver = {
.name = "k3-soc-thermal",
.of_match_table = of_k3_bandgap_match,
},
};
module_platform_driver(k3_bandgap_sensor_driver);
MODULE_DESCRIPTION("K3 bandgap temperature sensor driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");