/* * Copyright (c) 2011, NVIDIA Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include <linux/gpio.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/rfkill.h> #include <linux/platform_device.h> #include <linux/clk.h> #include <linux/slab.h> #include <linux/rfkill-gpio.h> enum rfkill_gpio_clk_state { UNSPECIFIED = 0, PWR_ENABLED, PWR_DISABLED }; #define PWR_CLK_SET(_RF, _EN) \ ((_RF)->pwr_clk_enabled = (!(_EN) ? PWR_ENABLED : PWR_DISABLED)) #define PWR_CLK_ENABLED(_RF) ((_RF)->pwr_clk_enabled == PWR_ENABLED) #define PWR_CLK_DISABLED(_RF) ((_RF)->pwr_clk_enabled != PWR_ENABLED) struct rfkill_gpio_data { struct rfkill_gpio_platform_data *pdata; struct rfkill *rfkill_dev; char *reset_name; char *shutdown_name; enum rfkill_gpio_clk_state pwr_clk_enabled; struct clk *pwr_clk; }; static int rfkill_gpio_set_power(void *data, bool blocked) { struct rfkill_gpio_data *rfkill = data; if (blocked) { if (gpio_is_valid(rfkill->pdata->shutdown_gpio)) gpio_direction_output(rfkill->pdata->shutdown_gpio, 0); if (gpio_is_valid(rfkill->pdata->reset_gpio)) gpio_direction_output(rfkill->pdata->reset_gpio, 0); if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill)) clk_disable(rfkill->pwr_clk); } else { if (rfkill->pwr_clk && PWR_CLK_DISABLED(rfkill)) clk_enable(rfkill->pwr_clk); if (gpio_is_valid(rfkill->pdata->reset_gpio)) gpio_direction_output(rfkill->pdata->reset_gpio, 1); if (gpio_is_valid(rfkill->pdata->shutdown_gpio)) gpio_direction_output(rfkill->pdata->shutdown_gpio, 1); } if (rfkill->pwr_clk) PWR_CLK_SET(rfkill, blocked); return 0; } static const struct rfkill_ops rfkill_gpio_ops = { .set_block = rfkill_gpio_set_power, }; static int rfkill_gpio_probe(struct platform_device *pdev) { struct rfkill_gpio_data *rfkill; struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data; int ret = 0; int len = 0; if (!pdata) { pr_warn("%s: No platform data specified\n", __func__); return -EINVAL; } /* make sure at-least one of the GPIO is defined and that * a name is specified for this instance */ if (!pdata->name || (!gpio_is_valid(pdata->reset_gpio) && !gpio_is_valid(pdata->shutdown_gpio))) { pr_warn("%s: invalid platform data\n", __func__); return -EINVAL; } rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL); if (!rfkill) return -ENOMEM; if (pdata->gpio_runtime_setup) { ret = pdata->gpio_runtime_setup(pdev); if (ret) { pr_warn("%s: can't set up gpio\n", __func__); goto fail_alloc; } } rfkill->pdata = pdata; len = strlen(pdata->name); rfkill->reset_name = kzalloc(len + 7, GFP_KERNEL); if (!rfkill->reset_name) { ret = -ENOMEM; goto fail_alloc; } rfkill->shutdown_name = kzalloc(len + 10, GFP_KERNEL); if (!rfkill->shutdown_name) { ret = -ENOMEM; goto fail_reset_name; } snprintf(rfkill->reset_name, len + 6 , "%s_reset", pdata->name); snprintf(rfkill->shutdown_name, len + 9, "%s_shutdown", pdata->name); if (pdata->power_clk_name) { rfkill->pwr_clk = clk_get(&pdev->dev, pdata->power_clk_name); if (IS_ERR(rfkill->pwr_clk)) { pr_warn("%s: can't find pwr_clk.\n", __func__); goto fail_shutdown_name; } } if (gpio_is_valid(pdata->reset_gpio)) { ret = gpio_request(pdata->reset_gpio, rfkill->reset_name); if (ret) { pr_warn("%s: failed to get reset gpio.\n", __func__); goto fail_clock; } } if (gpio_is_valid(pdata->shutdown_gpio)) { ret = gpio_request(pdata->shutdown_gpio, rfkill->shutdown_name); if (ret) { pr_warn("%s: failed to get shutdown gpio.\n", __func__); goto fail_reset; } } rfkill->rfkill_dev = rfkill_alloc(pdata->name, &pdev->dev, pdata->type, &rfkill_gpio_ops, rfkill); if (!rfkill->rfkill_dev) goto fail_shutdown; ret = rfkill_register(rfkill->rfkill_dev); if (ret < 0) goto fail_rfkill; platform_set_drvdata(pdev, rfkill); dev_info(&pdev->dev, "%s device registered.\n", pdata->name); return 0; fail_rfkill: rfkill_destroy(rfkill->rfkill_dev); fail_shutdown: if (gpio_is_valid(pdata->shutdown_gpio)) gpio_free(pdata->shutdown_gpio); fail_reset: if (gpio_is_valid(pdata->reset_gpio)) gpio_free(pdata->reset_gpio); fail_clock: if (rfkill->pwr_clk) clk_put(rfkill->pwr_clk); fail_shutdown_name: kfree(rfkill->shutdown_name); fail_reset_name: kfree(rfkill->reset_name); fail_alloc: kfree(rfkill); return ret; } static int rfkill_gpio_remove(struct platform_device *pdev) { struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data; if (pdata->gpio_runtime_close) pdata->gpio_runtime_close(pdev); rfkill_unregister(rfkill->rfkill_dev); rfkill_destroy(rfkill->rfkill_dev); if (gpio_is_valid(rfkill->pdata->shutdown_gpio)) gpio_free(rfkill->pdata->shutdown_gpio); if (gpio_is_valid(rfkill->pdata->reset_gpio)) gpio_free(rfkill->pdata->reset_gpio); if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill)) clk_disable(rfkill->pwr_clk); if (rfkill->pwr_clk) clk_put(rfkill->pwr_clk); kfree(rfkill->shutdown_name); kfree(rfkill->reset_name); kfree(rfkill); return 0; } static struct platform_driver rfkill_gpio_driver = { .probe = rfkill_gpio_probe, .remove = rfkill_gpio_remove, .driver = { .name = "rfkill_gpio", .owner = THIS_MODULE, }, }; module_platform_driver(rfkill_gpio_driver); MODULE_DESCRIPTION("gpio rfkill"); MODULE_AUTHOR("NVIDIA"); MODULE_LICENSE("GPL");