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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Access to GPOs on TWL6040 chip4 *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 23static 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 35static int twl6040gpo_get_direction(struct gpio_chip *chip, unsigned offset)36{37 return GPIO_LINE_DIRECTION_OUT;38}39 40static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned offset,41 int value)42{43 /* This only drives GPOs, and can't change direction */44 return 0;45}46 47static void twl6040gpo_set(struct gpio_chip *chip, unsigned offset, int value)48{49 struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);50 int ret;51 u8 gpoctl;52 53 ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);54 if (ret < 0)55 return;56 57 if (value)58 gpoctl = ret | BIT(offset);59 else60 gpoctl = ret & ~BIT(offset);61 62 twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl);63}64 65static struct gpio_chip twl6040gpo_chip = {66 .label = "twl6040",67 .owner = THIS_MODULE,68 .get = twl6040gpo_get,69 .direction_output = twl6040gpo_direction_out,70 .get_direction = twl6040gpo_get_direction,71 .set = twl6040gpo_set,72 .can_sleep = true,73};74 75/*----------------------------------------------------------------------*/76 77static int gpo_twl6040_probe(struct platform_device *pdev)78{79 struct device *twl6040_core_dev = pdev->dev.parent;80 struct twl6040 *twl6040 = dev_get_drvdata(twl6040_core_dev);81 int ret;82 83 device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));84 85 twl6040gpo_chip.base = -1;86 87 if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0)88 twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */89 else90 twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */91 92 twl6040gpo_chip.parent = &pdev->dev;93 94 ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, NULL);95 if (ret < 0) {96 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);97 twl6040gpo_chip.ngpio = 0;98 }99 100 return ret;101}102 103/* Note: this hardware lives inside an I2C-based multi-function device. */104MODULE_ALIAS("platform:twl6040-gpo");105 106static struct platform_driver gpo_twl6040_driver = {107 .driver = {108 .name = "twl6040-gpo",109 },110 .probe = gpo_twl6040_probe,111};112 113module_platform_driver(gpo_twl6040_driver);114 115MODULE_AUTHOR("Texas Instruments, Inc.");116MODULE_DESCRIPTION("GPO interface for TWL6040");117MODULE_LICENSE("GPL");118