1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/drivers/gpio/gpio-mb86s7x.c 4 * 5 * Copyright (C) 2015 Fujitsu Semiconductor Limited 6 * Copyright (C) 2015 Linaro Ltd. 7 */ 8 9 #include <linux/acpi.h> 10 #include <linux/io.h> 11 #include <linux/init.h> 12 #include <linux/clk.h> 13 #include <linux/mod_devicetable.h> 14 #include <linux/module.h> 15 #include <linux/err.h> 16 #include <linux/errno.h> 17 #include <linux/ioport.h> 18 #include <linux/gpio/driver.h> 19 #include <linux/platform_device.h> 20 #include <linux/spinlock.h> 21 #include <linux/slab.h> 22 23 #include "gpiolib.h" 24 #include "gpiolib-acpi.h" 25 26 /* 27 * Only first 8bits of a register correspond to each pin, 28 * so there are 4 registers for 32 pins. 29 */ 30 #define PDR(x) (0x0 + x / 8 * 4) 31 #define DDR(x) (0x10 + x / 8 * 4) 32 #define PFR(x) (0x20 + x / 8 * 4) 33 34 #define OFFSET(x) BIT((x) % 8) 35 36 struct mb86s70_gpio_chip { 37 struct gpio_chip gc; 38 void __iomem *base; 39 struct clk *clk; 40 spinlock_t lock; 41 }; 42 43 static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio) 44 { 45 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 46 unsigned long flags; 47 u32 val; 48 49 spin_lock_irqsave(&gchip->lock, flags); 50 51 val = readl(gchip->base + PFR(gpio)); 52 val &= ~OFFSET(gpio); 53 writel(val, gchip->base + PFR(gpio)); 54 55 spin_unlock_irqrestore(&gchip->lock, flags); 56 57 return 0; 58 } 59 60 static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio) 61 { 62 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 63 unsigned long flags; 64 u32 val; 65 66 spin_lock_irqsave(&gchip->lock, flags); 67 68 val = readl(gchip->base + PFR(gpio)); 69 val |= OFFSET(gpio); 70 writel(val, gchip->base + PFR(gpio)); 71 72 spin_unlock_irqrestore(&gchip->lock, flags); 73 } 74 75 static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio) 76 { 77 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 78 unsigned long flags; 79 unsigned char val; 80 81 spin_lock_irqsave(&gchip->lock, flags); 82 83 val = readl(gchip->base + DDR(gpio)); 84 val &= ~OFFSET(gpio); 85 writel(val, gchip->base + DDR(gpio)); 86 87 spin_unlock_irqrestore(&gchip->lock, flags); 88 89 return 0; 90 } 91 92 static int mb86s70_gpio_direction_output(struct gpio_chip *gc, 93 unsigned gpio, int value) 94 { 95 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 96 unsigned long flags; 97 unsigned char val; 98 99 spin_lock_irqsave(&gchip->lock, flags); 100 101 val = readl(gchip->base + PDR(gpio)); 102 if (value) 103 val |= OFFSET(gpio); 104 else 105 val &= ~OFFSET(gpio); 106 writel(val, gchip->base + PDR(gpio)); 107 108 val = readl(gchip->base + DDR(gpio)); 109 val |= OFFSET(gpio); 110 writel(val, gchip->base + DDR(gpio)); 111 112 spin_unlock_irqrestore(&gchip->lock, flags); 113 114 return 0; 115 } 116 117 static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio) 118 { 119 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 120 121 return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio)); 122 } 123 124 static void mb86s70_gpio_set(struct gpio_chip *gc, unsigned gpio, int value) 125 { 126 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 127 unsigned long flags; 128 unsigned char val; 129 130 spin_lock_irqsave(&gchip->lock, flags); 131 132 val = readl(gchip->base + PDR(gpio)); 133 if (value) 134 val |= OFFSET(gpio); 135 else 136 val &= ~OFFSET(gpio); 137 writel(val, gchip->base + PDR(gpio)); 138 139 spin_unlock_irqrestore(&gchip->lock, flags); 140 } 141 142 static int mb86s70_gpio_to_irq(struct gpio_chip *gc, unsigned int offset) 143 { 144 int irq, index; 145 146 for (index = 0;; index++) { 147 irq = platform_get_irq(to_platform_device(gc->parent), index); 148 if (irq < 0) 149 return irq; 150 if (irq == 0) 151 break; 152 if (irq_get_irq_data(irq)->hwirq == offset) 153 return irq; 154 } 155 return -EINVAL; 156 } 157 158 static int mb86s70_gpio_probe(struct platform_device *pdev) 159 { 160 struct mb86s70_gpio_chip *gchip; 161 int ret; 162 163 gchip = devm_kzalloc(&pdev->dev, sizeof(*gchip), GFP_KERNEL); 164 if (gchip == NULL) 165 return -ENOMEM; 166 167 platform_set_drvdata(pdev, gchip); 168 169 gchip->base = devm_platform_ioremap_resource(pdev, 0); 170 if (IS_ERR(gchip->base)) 171 return PTR_ERR(gchip->base); 172 173 gchip->clk = devm_clk_get_optional(&pdev->dev, NULL); 174 if (IS_ERR(gchip->clk)) 175 return PTR_ERR(gchip->clk); 176 177 ret = clk_prepare_enable(gchip->clk); 178 if (ret) 179 return ret; 180 181 spin_lock_init(&gchip->lock); 182 183 gchip->gc.direction_output = mb86s70_gpio_direction_output; 184 gchip->gc.direction_input = mb86s70_gpio_direction_input; 185 gchip->gc.request = mb86s70_gpio_request; 186 gchip->gc.free = mb86s70_gpio_free; 187 gchip->gc.get = mb86s70_gpio_get; 188 gchip->gc.set = mb86s70_gpio_set; 189 gchip->gc.to_irq = mb86s70_gpio_to_irq; 190 gchip->gc.label = dev_name(&pdev->dev); 191 gchip->gc.ngpio = 32; 192 gchip->gc.owner = THIS_MODULE; 193 gchip->gc.parent = &pdev->dev; 194 gchip->gc.base = -1; 195 196 ret = gpiochip_add_data(&gchip->gc, gchip); 197 if (ret) { 198 dev_err(&pdev->dev, "couldn't register gpio driver\n"); 199 clk_disable_unprepare(gchip->clk); 200 return ret; 201 } 202 203 acpi_gpiochip_request_interrupts(&gchip->gc); 204 205 return 0; 206 } 207 208 static int mb86s70_gpio_remove(struct platform_device *pdev) 209 { 210 struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev); 211 212 acpi_gpiochip_free_interrupts(&gchip->gc); 213 gpiochip_remove(&gchip->gc); 214 clk_disable_unprepare(gchip->clk); 215 216 return 0; 217 } 218 219 static const struct of_device_id mb86s70_gpio_dt_ids[] = { 220 { .compatible = "fujitsu,mb86s70-gpio" }, 221 { /* sentinel */ } 222 }; 223 MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids); 224 225 #ifdef CONFIG_ACPI 226 static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = { 227 { "SCX0007" }, 228 { /* sentinel */ } 229 }; 230 MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids); 231 #endif 232 233 static struct platform_driver mb86s70_gpio_driver = { 234 .driver = { 235 .name = "mb86s70-gpio", 236 .of_match_table = mb86s70_gpio_dt_ids, 237 .acpi_match_table = ACPI_PTR(mb86s70_gpio_acpi_ids), 238 }, 239 .probe = mb86s70_gpio_probe, 240 .remove = mb86s70_gpio_remove, 241 }; 242 module_platform_driver(mb86s70_gpio_driver); 243 244 MODULE_DESCRIPTION("MB86S7x GPIO Driver"); 245 MODULE_ALIAS("platform:mb86s70-gpio"); 246 MODULE_LICENSE("GPL"); 247