mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 09:15:11 +07:00
108 lines
2.5 KiB
C
108 lines
2.5 KiB
C
|
/*
|
||
|
|
* STM32 Low-Power Timer parent driver.
|
||
|
|
*
|
||
|
|
* Copyright (C) STMicroelectronics 2017
|
||
|
|
*
|
||
|
|
* Author: Fabrice Gasnier <fabrice.gasnier@st.com>
|
||
|
|
*
|
||
|
|
* Inspired by Benjamin Gaignard's stm32-timers driver
|
||
|
|
*
|
||
|
|
* License terms: GNU General Public License (GPL), version 2
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/mfd/stm32-lptimer.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/of_platform.h>
|
||
|
|
|
||
|
|
#define STM32_LPTIM_MAX_REGISTER 0x3fc
|
||
|
|
|
||
|
|
static const struct regmap_config stm32_lptimer_regmap_cfg = {
|
||
|
|
.reg_bits = 32,
|
||
|
|
.val_bits = 32,
|
||
|
|
.reg_stride = sizeof(u32),
|
||
|
|
.max_register = STM32_LPTIM_MAX_REGISTER,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int stm32_lptimer_detect_encoder(struct stm32_lptimer *ddata)
|
||
|
|
{
|
||
|
|
u32 val;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Quadrature encoder mode bit can only be written and read back when
|
||
|
|
* Low-Power Timer supports it.
|
||
|
|
*/
|
||
|
|
ret = regmap_update_bits(ddata->regmap, STM32_LPTIM_CFGR,
|
||
|
|
STM32_LPTIM_ENC, STM32_LPTIM_ENC);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ret = regmap_read(ddata->regmap, STM32_LPTIM_CFGR, &val);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ret = regmap_update_bits(ddata->regmap, STM32_LPTIM_CFGR,
|
||
|
|
STM32_LPTIM_ENC, 0);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ddata->has_encoder = !!(val & STM32_LPTIM_ENC);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int stm32_lptimer_probe(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct device *dev = &pdev->dev;
|
||
|
|
struct stm32_lptimer *ddata;
|
||
|
|
struct resource *res;
|
||
|
|
void __iomem *mmio;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
|
||
|
|
if (!ddata)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
|
mmio = devm_ioremap_resource(dev, res);
|
||
|
|
if (IS_ERR(mmio))
|
||
|
|
return PTR_ERR(mmio);
|
||
|
|
|
||
|
|
ddata->regmap = devm_regmap_init_mmio_clk(dev, "mux", mmio,
|
||
|
|
&stm32_lptimer_regmap_cfg);
|
||
|
|
if (IS_ERR(ddata->regmap))
|
||
|
|
return PTR_ERR(ddata->regmap);
|
||
|
|
|
||
|
|
ddata->clk = devm_clk_get(dev, NULL);
|
||
|
|
if (IS_ERR(ddata->clk))
|
||
|
|
return PTR_ERR(ddata->clk);
|
||
|
|
|
||
|
|
ret = stm32_lptimer_detect_encoder(ddata);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
platform_set_drvdata(pdev, ddata);
|
||
|
|
|
||
|
|
return devm_of_platform_populate(&pdev->dev);
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct of_device_id stm32_lptimer_of_match[] = {
|
||
|
|
{ .compatible = "st,stm32-lptimer", },
|
||
|
|
{},
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, stm32_lptimer_of_match);
|
||
|
|
|
||
|
|
static struct platform_driver stm32_lptimer_driver = {
|
||
|
|
.probe = stm32_lptimer_probe,
|
||
|
|
.driver = {
|
||
|
|
.name = "stm32-lptimer",
|
||
|
|
.of_match_table = stm32_lptimer_of_match,
|
||
|
|
},
|
||
|
|
};
|
||
|
|
module_platform_driver(stm32_lptimer_driver);
|
||
|
|
|
||
|
|
MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
|
||
|
|
MODULE_DESCRIPTION("STMicroelectronics STM32 Low-Power Timer");
|
||
|
|
MODULE_ALIAS("platform:stm32-lptimer");
|
||
|
|
MODULE_LICENSE("GPL v2");
|