LXR linux/drivers/mfd/stm32-timers.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) STMicroelectronics 2016
   4 * Author: Benjamin Gaignard <benjamin.gaignard@st.com>
   5 */
   6
   7#include <linux/mfd/stm32-timers.h>
   8#include <linux/module.h>
   9#include <linux/of_platform.h>
  10#include <linux/reset.h>
  11
  12static const struct regmap_config stm32_timers_regmap_cfg = {
  13        .reg_bits = 32,
  14        .val_bits = 32,
  15        .reg_stride = sizeof(u32),
  16        .max_register = 0x3fc,
  17};
  18
  19static void stm32_timers_get_arr_size(struct stm32_timers *ddata)
  20{
  21        /*
  22         * Only the available bits will be written so when readback
  23         * we get the maximum value of auto reload register
  24         */
  25        regmap_write(ddata->regmap, TIM_ARR, ~0L);
  26        regmap_read(ddata->regmap, TIM_ARR, &ddata->max_arr);
  27        regmap_write(ddata->regmap, TIM_ARR, 0x0);
  28}
  29
  30static int stm32_timers_probe(struct platform_device *pdev)
  31{
  32        struct device *dev = &pdev->dev;
  33        struct stm32_timers *ddata;
  34        struct resource *res;
  35        void __iomem *mmio;
  36
  37        ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
  38        if (!ddata)
  39                return -ENOMEM;
  40
  41        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  42        mmio = devm_ioremap_resource(dev, res);
  43        if (IS_ERR(mmio))
  44                return PTR_ERR(mmio);
  45
  46        ddata->regmap = devm_regmap_init_mmio_clk(dev, "int", mmio,
  47                                                  &stm32_timers_regmap_cfg);
  48        if (IS_ERR(ddata->regmap))
  49                return PTR_ERR(ddata->regmap);
  50
  51        ddata->clk = devm_clk_get(dev, NULL);
  52        if (IS_ERR(ddata->clk))
  53                return PTR_ERR(ddata->clk);
  54
  55        stm32_timers_get_arr_size(ddata);
  56
  57        platform_set_drvdata(pdev, ddata);
  58
  59        return devm_of_platform_populate(&pdev->dev);
  60}
  61
  62static const struct of_device_id stm32_timers_of_match[] = {
  63        { .compatible = "st,stm32-timers", },
  64        { /* end node */ },
  65};
  66MODULE_DEVICE_TABLE(of, stm32_timers_of_match);
  67
  68static struct platform_driver stm32_timers_driver = {
  69        .probe = stm32_timers_probe,
  70        .driver = {
  71                .name = "stm32-timers",
  72                .of_match_table = stm32_timers_of_match,
  73        },
  74};
  75module_platform_driver(stm32_timers_driver);
  76
  77MODULE_DESCRIPTION("STMicroelectronics STM32 Timers");
  78MODULE_LICENSE("GPL v2");
  79