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 = gpiochip_get_data(chip); 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 return GPIO_LINE_DIRECTION_OUT; 38 } 39 40 static int twl6040gpo_set(struct gpio_chip *chip, unsigned int offset, 41 int value) 42 { 43 struct twl6040 *twl6040 = gpiochip_get_data(chip); 44 int ret; 45 u8 gpoctl; 46 47 ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL); 48 if (ret < 0) 49 return ret; 50 51 if (value) 52 gpoctl = ret | BIT(offset); 53 else 54 gpoctl = ret & ~BIT(offset); 55 56 return twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl); 57 } 58 59 static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned int offset, 60 int value) 61 { 62 /* This only drives GPOs, and can't change direction */ 63 return twl6040gpo_set(chip, offset, value); 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 device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent)); 85 86 twl6040gpo_chip.base = -1; 87 88 if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0) 89 twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */ 90 else 91 twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */ 92 93 twl6040gpo_chip.parent = &pdev->dev; 94 95 ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, twl6040); 96 if (ret < 0) { 97 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); 98 twl6040gpo_chip.ngpio = 0; 99 } 100 101 return ret; 102 } 103 104 /* Note: this hardware lives inside an I2C-based multi-function device. */ 105 MODULE_ALIAS("platform:twl6040-gpo"); 106 107 static struct platform_driver gpo_twl6040_driver = { 108 .driver = { 109 .name = "twl6040-gpo", 110 }, 111 .probe = gpo_twl6040_probe, 112 }; 113 114 module_platform_driver(gpo_twl6040_driver); 115 116 MODULE_AUTHOR("Texas Instruments, Inc."); 117 MODULE_DESCRIPTION("GPO interface for TWL6040"); 118 MODULE_LICENSE("GPL"); 119