/* * LP5521/LP5523/LP55231 Common Driver * * Copyright 2012 Texas Instruments * * Author: Milo(Woogyom) Kim * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Derived from leds-lp5521.c, leds-lp5523.c */ #include #include #include #include #include #include "leds-lp55xx-common.h" static void lp55xx_reset_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; u8 addr = cfg->reset.addr; u8 val = cfg->reset.val; /* no error checking here because no ACK from the device after reset */ lp55xx_write(chip, addr, val); } static int lp55xx_detect_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; u8 addr = cfg->enable.addr; u8 val = cfg->enable.val; int ret; ret = lp55xx_write(chip, addr, val); if (ret) return ret; usleep_range(1000, 2000); ret = lp55xx_read(chip, addr, &val); if (ret) return ret; if (val != cfg->enable.val) return -ENODEV; return 0; } static int lp55xx_post_init_device(struct lp55xx_chip *chip) { struct lp55xx_device_config *cfg = chip->cfg; if (!cfg->post_init_device) return 0; return cfg->post_init_device(chip); } int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val) { return i2c_smbus_write_byte_data(chip->cl, reg, val); } EXPORT_SYMBOL_GPL(lp55xx_write); int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val) { s32 ret; ret = i2c_smbus_read_byte_data(chip->cl, reg); if (ret < 0) return ret; *val = ret; return 0; } EXPORT_SYMBOL_GPL(lp55xx_read); int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val) { int ret; u8 tmp; ret = lp55xx_read(chip, reg, &tmp); if (ret) return ret; tmp &= ~mask; tmp |= val & mask; return lp55xx_write(chip, reg, tmp); } EXPORT_SYMBOL_GPL(lp55xx_update_bits); int lp55xx_init_device(struct lp55xx_chip *chip) { struct lp55xx_platform_data *pdata; struct lp55xx_device_config *cfg; struct device *dev = &chip->cl->dev; int ret = 0; WARN_ON(!chip); pdata = chip->pdata; cfg = chip->cfg; if (!pdata || !cfg) return -EINVAL; if (pdata->setup_resources) { ret = pdata->setup_resources(); if (ret < 0) { dev_err(dev, "setup resoure err: %d\n", ret); goto err; } } if (pdata->enable) { pdata->enable(0); usleep_range(1000, 2000); /* Keep enable down at least 1ms */ pdata->enable(1); usleep_range(1000, 2000); /* 500us abs min. */ } lp55xx_reset_device(chip); /* * Exact value is not available. 10 - 20ms * appears to be enough for reset. */ usleep_range(10000, 20000); ret = lp55xx_detect_device(chip); if (ret) { dev_err(dev, "device detection err: %d\n", ret); goto err; } /* chip specific initialization */ ret = lp55xx_post_init_device(chip); if (ret) { dev_err(dev, "post init device err: %d\n", ret); goto err_post_init; } return 0; err_post_init: if (pdata->enable) pdata->enable(0); if (pdata->release_resources) pdata->release_resources(); err: return ret; } EXPORT_SYMBOL_GPL(lp55xx_init_device); MODULE_AUTHOR("Milo Kim "); MODULE_DESCRIPTION("LP55xx Common Driver"); MODULE_LICENSE("GPL");