1 /* 2 * Copyright (C) STMicroelectronics 2016 3 * 4 * Author: Benjamin Gaignard <benjamin.gaignard@st.com> 5 * 6 * License terms: GNU General Public License (GPL), version 2 7 */ 8 9 #include <linux/mfd/stm32-timers.h> 10 #include <linux/module.h> 11 #include <linux/of_platform.h> 12 #include <linux/reset.h> 13 14 static const struct regmap_config stm32_timers_regmap_cfg = { 15 .reg_bits = 32, 16 .val_bits = 32, 17 .reg_stride = sizeof(u32), 18 .max_register = 0x3fc, 19 }; 20 21 static void stm32_timers_get_arr_size(struct stm32_timers *ddata) 22 { 23 /* 24 * Only the available bits will be written so when readback 25 * we get the maximum value of auto reload register 26 */ 27 regmap_write(ddata->regmap, TIM_ARR, ~0L); 28 regmap_read(ddata->regmap, TIM_ARR, &ddata->max_arr); 29 regmap_write(ddata->regmap, TIM_ARR, 0x0); 30 } 31 32 static int stm32_timers_probe(struct platform_device *pdev) 33 { 34 struct device *dev = &pdev->dev; 35 struct stm32_timers *ddata; 36 struct resource *res; 37 void __iomem *mmio; 38 39 ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); 40 if (!ddata) 41 return -ENOMEM; 42 43 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 44 mmio = devm_ioremap_resource(dev, res); 45 if (IS_ERR(mmio)) 46 return PTR_ERR(mmio); 47 48 ddata->regmap = devm_regmap_init_mmio_clk(dev, "int", mmio, 49 &stm32_timers_regmap_cfg); 50 if (IS_ERR(ddata->regmap)) 51 return PTR_ERR(ddata->regmap); 52 53 ddata->clk = devm_clk_get(dev, NULL); 54 if (IS_ERR(ddata->clk)) 55 return PTR_ERR(ddata->clk); 56 57 stm32_timers_get_arr_size(ddata); 58 59 platform_set_drvdata(pdev, ddata); 60 61 return devm_of_platform_populate(&pdev->dev); 62 } 63 64 static const struct of_device_id stm32_timers_of_match[] = { 65 { .compatible = "st,stm32-timers", }, 66 { /* end node */ }, 67 }; 68 MODULE_DEVICE_TABLE(of, stm32_timers_of_match); 69 70 static struct platform_driver stm32_timers_driver = { 71 .probe = stm32_timers_probe, 72 .driver = { 73 .name = "stm32-timers", 74 .of_match_table = stm32_timers_of_match, 75 }, 76 }; 77 module_platform_driver(stm32_timers_driver); 78 79 MODULE_DESCRIPTION("STMicroelectronics STM32 Timers"); 80 MODULE_LICENSE("GPL v2"); 81