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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /sound/soc/codecs/l3.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sound/soc/codecs/l3.c')
-rw-r--r-- | sound/soc/codecs/l3.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/sound/soc/codecs/l3.c b/sound/soc/codecs/l3.c new file mode 100644 index 000000000..a10ea3c71 --- /dev/null +++ b/sound/soc/codecs/l3.c @@ -0,0 +1,138 @@ +/* + * L3 code + * + * Copyright (C) 2008, Christian Pellegrin <chripell@evolware.org> + * + * 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. + * + * + * based on: + * + * L3 bus algorithm module. + * + * Copyright (C) 2001 Russell King, All Rights Reserved. + * + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/gpio.h> + +#include <sound/l3.h> + +/* + * Send one byte of data to the chip. Data is latched into the chip on + * the rising edge of the clock. + */ +static void sendbyte(struct l3_pins *adap, unsigned int byte) +{ + int i; + + for (i = 0; i < 8; i++) { + adap->setclk(adap, 0); + udelay(adap->data_hold); + adap->setdat(adap, byte & 1); + udelay(adap->data_setup); + adap->setclk(adap, 1); + udelay(adap->clock_high); + byte >>= 1; + } +} + +/* + * Send a set of bytes to the chip. We need to pulse the MODE line + * between each byte, but never at the start nor at the end of the + * transfer. + */ +static void sendbytes(struct l3_pins *adap, const u8 *buf, + int len) +{ + int i; + + for (i = 0; i < len; i++) { + if (i) { + udelay(adap->mode_hold); + adap->setmode(adap, 0); + udelay(adap->mode); + } + adap->setmode(adap, 1); + udelay(adap->mode_setup); + sendbyte(adap, buf[i]); + } +} + +int l3_write(struct l3_pins *adap, u8 addr, u8 *data, int len) +{ + adap->setclk(adap, 1); + adap->setdat(adap, 1); + adap->setmode(adap, 1); + udelay(adap->mode); + + adap->setmode(adap, 0); + udelay(adap->mode_setup); + sendbyte(adap, addr); + udelay(adap->mode_hold); + + sendbytes(adap, data, len); + + adap->setclk(adap, 1); + adap->setdat(adap, 1); + adap->setmode(adap, 0); + + return len; +} +EXPORT_SYMBOL_GPL(l3_write); + + +static void l3_set_clk(struct l3_pins *adap, int val) +{ + gpio_set_value(adap->gpio_clk, val); +} + +static void l3_set_data(struct l3_pins *adap, int val) +{ + gpio_set_value(adap->gpio_data, val); +} + +static void l3_set_mode(struct l3_pins *adap, int val) +{ + gpio_set_value(adap->gpio_mode, val); +} + +int l3_set_gpio_ops(struct device *dev, struct l3_pins *adap) +{ + int ret; + + if (!adap->use_gpios) + return -EINVAL; + + ret = devm_gpio_request_one(dev, adap->gpio_data, + GPIOF_OUT_INIT_LOW, "l3_data"); + if (ret < 0) + return ret; + adap->setdat = l3_set_data; + + ret = devm_gpio_request_one(dev, adap->gpio_clk, + GPIOF_OUT_INIT_LOW, "l3_clk"); + if (ret < 0) + return ret; + adap->setclk = l3_set_clk; + + ret = devm_gpio_request_one(dev, adap->gpio_mode, + GPIOF_OUT_INIT_LOW, "l3_mode"); + if (ret < 0) + return ret; + adap->setmode = l3_set_mode; + + return 0; +} +EXPORT_SYMBOL_GPL(l3_set_gpio_ops); + +MODULE_DESCRIPTION("L3 bit-banging driver"); +MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>"); +MODULE_LICENSE("GPL"); |