1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Access to GPOs on TWL6040 chip 4 * 5 * Copyright (C) 2012 Texas Instruments, Inc. 6 * 7 * Authors: 8 * Sergio Aguirre <saaguirre@ti.com> 9 * Peter Ujfalusi <peter.ujfalusi@ti.com> 10 */ 11 12 #include <linux/module.h> 13 #include <linux/init.h> 14 #include <linux/kthread.h> 15 #include <linux/irq.h> 16 #include <linux/gpio/driver.h> 17 #include <linux/platform_device.h> 18 #include <linux/bitops.h> 19 #include <linux/of.h> 20 21 #include <linux/mfd/twl6040.h> 22 23 static int twl6040gpo_get(struct gpio_chip *chip, unsigned offset) 24 { 25 struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent); 26 int ret = 0; 27 28 ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL); 29 if (ret < 0) 30 return ret; 31 32 return !!(ret & BIT(offset)); 33 } 34 35 static int twl6040gpo_get_direction(struct gpio_chip *chip, unsigned offset) 36 { 37 /* This means "out" */ 38 return 0; 39 } 40 41 static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned offset, 42 int value) 43 { 44 /* This only drives GPOs, and can't change direction */ 45 return 0; 46 } 47 48 static void twl6040gpo_set(struct gpio_chip *chip, unsigned offset, int value) 49 { 50 struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent); 51 int ret; 52 u8 gpoctl; 53 54 ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL); 55 if (ret < 0) 56 return; 57 58 if (value) 59 gpoctl = ret | BIT(offset); 60 else 61 gpoctl = ret & ~BIT(offset); 62 63 twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl); 64 } 65 66 static struct gpio_chip twl6040gpo_chip = { 67 .label = "twl6040", 68 .owner = THIS_MODULE, 69 .get = twl6040gpo_get, 70 .direction_output = twl6040gpo_direction_out, 71 .get_direction = twl6040gpo_get_direction, 72 .set = twl6040gpo_set, 73 .can_sleep = true, 74 }; 75 76 /*----------------------------------------------------------------------*/ 77 78 static int gpo_twl6040_probe(struct platform_device *pdev) 79 { 80 struct device *twl6040_core_dev = pdev->dev.parent; 81 struct twl6040 *twl6040 = dev_get_drvdata(twl6040_core_dev); 82 int ret; 83 84 twl6040gpo_chip.base = -1; 85 86 if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0) 87 twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */ 88 else 89 twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */ 90 91 twl6040gpo_chip.parent = &pdev->dev; 92 #ifdef CONFIG_OF_GPIO 93 twl6040gpo_chip.of_node = twl6040_core_dev->of_node; 94 #endif 95 96 ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, NULL); 97 if (ret < 0) { 98 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); 99 twl6040gpo_chip.ngpio = 0; 100 } 101 102 return ret; 103 } 104 105 /* Note: this hardware lives inside an I2C-based multi-function device. */ 106 MODULE_ALIAS("platform:twl6040-gpo"); 107 108 static struct platform_driver gpo_twl6040_driver = { 109 .driver = { 110 .name = "twl6040-gpo", 111 }, 112 .probe = gpo_twl6040_probe, 113 }; 114 115 module_platform_driver(gpo_twl6040_driver); 116 117 MODULE_AUTHOR("Texas Instruments, Inc."); 118 MODULE_DESCRIPTION("GPO interface for TWL6040"); 119 MODULE_LICENSE("GPL"); 120