1 /* 2 * linux/drivers/gpio/gpio-mb86s7x.c 3 * 4 * Copyright (C) 2015 Fujitsu Semiconductor Limited 5 * Copyright (C) 2015 Linaro Ltd. 6 * 7 * This program is free software: you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation, version 2 of the License. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 17 #include <linux/acpi.h> 18 #include <linux/io.h> 19 #include <linux/init.h> 20 #include <linux/clk.h> 21 #include <linux/module.h> 22 #include <linux/err.h> 23 #include <linux/errno.h> 24 #include <linux/ioport.h> 25 #include <linux/of_device.h> 26 #include <linux/gpio/driver.h> 27 #include <linux/platform_device.h> 28 #include <linux/spinlock.h> 29 #include <linux/slab.h> 30 31 #include "gpiolib.h" 32 33 /* 34 * Only first 8bits of a register correspond to each pin, 35 * so there are 4 registers for 32 pins. 36 */ 37 #define PDR(x) (0x0 + x / 8 * 4) 38 #define DDR(x) (0x10 + x / 8 * 4) 39 #define PFR(x) (0x20 + x / 8 * 4) 40 41 #define OFFSET(x) BIT((x) % 8) 42 43 struct mb86s70_gpio_chip { 44 struct gpio_chip gc; 45 void __iomem *base; 46 struct clk *clk; 47 spinlock_t lock; 48 }; 49 50 static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio) 51 { 52 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 53 unsigned long flags; 54 u32 val; 55 56 spin_lock_irqsave(&gchip->lock, flags); 57 58 val = readl(gchip->base + PFR(gpio)); 59 val &= ~OFFSET(gpio); 60 writel(val, gchip->base + PFR(gpio)); 61 62 spin_unlock_irqrestore(&gchip->lock, flags); 63 64 return 0; 65 } 66 67 static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio) 68 { 69 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 70 unsigned long flags; 71 u32 val; 72 73 spin_lock_irqsave(&gchip->lock, flags); 74 75 val = readl(gchip->base + PFR(gpio)); 76 val |= OFFSET(gpio); 77 writel(val, gchip->base + PFR(gpio)); 78 79 spin_unlock_irqrestore(&gchip->lock, flags); 80 } 81 82 static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio) 83 { 84 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 85 unsigned long flags; 86 unsigned char val; 87 88 spin_lock_irqsave(&gchip->lock, flags); 89 90 val = readl(gchip->base + DDR(gpio)); 91 val &= ~OFFSET(gpio); 92 writel(val, gchip->base + DDR(gpio)); 93 94 spin_unlock_irqrestore(&gchip->lock, flags); 95 96 return 0; 97 } 98 99 static int mb86s70_gpio_direction_output(struct gpio_chip *gc, 100 unsigned gpio, int value) 101 { 102 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 103 unsigned long flags; 104 unsigned char val; 105 106 spin_lock_irqsave(&gchip->lock, flags); 107 108 val = readl(gchip->base + PDR(gpio)); 109 if (value) 110 val |= OFFSET(gpio); 111 else 112 val &= ~OFFSET(gpio); 113 writel(val, gchip->base + PDR(gpio)); 114 115 val = readl(gchip->base + DDR(gpio)); 116 val |= OFFSET(gpio); 117 writel(val, gchip->base + DDR(gpio)); 118 119 spin_unlock_irqrestore(&gchip->lock, flags); 120 121 return 0; 122 } 123 124 static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio) 125 { 126 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 127 128 return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio)); 129 } 130 131 static void mb86s70_gpio_set(struct gpio_chip *gc, unsigned gpio, int value) 132 { 133 struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc); 134 unsigned long flags; 135 unsigned char val; 136 137 spin_lock_irqsave(&gchip->lock, flags); 138 139 val = readl(gchip->base + PDR(gpio)); 140 if (value) 141 val |= OFFSET(gpio); 142 else 143 val &= ~OFFSET(gpio); 144 writel(val, gchip->base + PDR(gpio)); 145 146 spin_unlock_irqrestore(&gchip->lock, flags); 147 } 148 149 static int mb86s70_gpio_to_irq(struct gpio_chip *gc, unsigned int offset) 150 { 151 int irq, index; 152 153 for (index = 0;; index++) { 154 irq = platform_get_irq(to_platform_device(gc->parent), index); 155 if (irq <= 0) 156 break; 157 if (irq_get_irq_data(irq)->hwirq == offset) 158 return irq; 159 } 160 return -EINVAL; 161 } 162 163 static int mb86s70_gpio_probe(struct platform_device *pdev) 164 { 165 struct mb86s70_gpio_chip *gchip; 166 int ret; 167 168 gchip = devm_kzalloc(&pdev->dev, sizeof(*gchip), GFP_KERNEL); 169 if (gchip == NULL) 170 return -ENOMEM; 171 172 platform_set_drvdata(pdev, gchip); 173 174 gchip->base = devm_platform_ioremap_resource(pdev, 0); 175 if (IS_ERR(gchip->base)) 176 return PTR_ERR(gchip->base); 177 178 if (!has_acpi_companion(&pdev->dev)) { 179 gchip->clk = devm_clk_get(&pdev->dev, NULL); 180 if (IS_ERR(gchip->clk)) 181 return PTR_ERR(gchip->clk); 182 183 ret = clk_prepare_enable(gchip->clk); 184 if (ret) 185 return ret; 186 } 187 188 spin_lock_init(&gchip->lock); 189 190 gchip->gc.direction_output = mb86s70_gpio_direction_output; 191 gchip->gc.direction_input = mb86s70_gpio_direction_input; 192 gchip->gc.request = mb86s70_gpio_request; 193 gchip->gc.free = mb86s70_gpio_free; 194 gchip->gc.get = mb86s70_gpio_get; 195 gchip->gc.set = mb86s70_gpio_set; 196 gchip->gc.label = dev_name(&pdev->dev); 197 gchip->gc.ngpio = 32; 198 gchip->gc.owner = THIS_MODULE; 199 gchip->gc.parent = &pdev->dev; 200 gchip->gc.base = -1; 201 202 if (has_acpi_companion(&pdev->dev)) 203 gchip->gc.to_irq = mb86s70_gpio_to_irq; 204 205 ret = gpiochip_add_data(&gchip->gc, gchip); 206 if (ret) { 207 dev_err(&pdev->dev, "couldn't register gpio driver\n"); 208 clk_disable_unprepare(gchip->clk); 209 return ret; 210 } 211 212 if (has_acpi_companion(&pdev->dev)) 213 acpi_gpiochip_request_interrupts(&gchip->gc); 214 215 return 0; 216 } 217 218 static int mb86s70_gpio_remove(struct platform_device *pdev) 219 { 220 struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev); 221 222 if (has_acpi_companion(&pdev->dev)) 223 acpi_gpiochip_free_interrupts(&gchip->gc); 224 gpiochip_remove(&gchip->gc); 225 clk_disable_unprepare(gchip->clk); 226 227 return 0; 228 } 229 230 static const struct of_device_id mb86s70_gpio_dt_ids[] = { 231 { .compatible = "fujitsu,mb86s70-gpio" }, 232 { /* sentinel */ } 233 }; 234 MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids); 235 236 #ifdef CONFIG_ACPI 237 static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = { 238 { "SCX0007" }, 239 { /* sentinel */ } 240 }; 241 MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids); 242 #endif 243 244 static struct platform_driver mb86s70_gpio_driver = { 245 .driver = { 246 .name = "mb86s70-gpio", 247 .of_match_table = mb86s70_gpio_dt_ids, 248 .acpi_match_table = ACPI_PTR(mb86s70_gpio_acpi_ids), 249 }, 250 .probe = mb86s70_gpio_probe, 251 .remove = mb86s70_gpio_remove, 252 }; 253 module_platform_driver(mb86s70_gpio_driver); 254 255 MODULE_DESCRIPTION("MB86S7x GPIO Driver"); 256 MODULE_ALIAS("platform:mb86s70-gpio"); 257 MODULE_LICENSE("GPL"); 258