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mux: adgs1408: new driver for Analog Devices ADGS1408/1409 mux
This patch adds basic support for Analog Device ADGS1408/09 SPI mux controller. The device is probed and set to a disabled state. It uses the new mux controller framework. Signed-off-by: Mircea Caprioru <[email protected]> Signed-off-by: Peter Rosin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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// SPDX-License-Identifier: GPL-2.0-or-later | ||
/* | ||
* ADGS1408/ADGS1409 SPI MUX driver | ||
* | ||
* Copyright 2018 Analog Devices Inc. | ||
*/ | ||
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#include <linux/err.h> | ||
#include <linux/module.h> | ||
#include <linux/mux/driver.h> | ||
#include <linux/of_platform.h> | ||
#include <linux/property.h> | ||
#include <linux/spi/spi.h> | ||
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#define ADGS1408_SW_DATA (0x01) | ||
#define ADGS1408_REG_READ(reg) ((reg) | 0x80) | ||
#define ADGS1408_DISABLE (0x00) | ||
#define ADGS1408_MUX(state) (((state) << 1) | 1) | ||
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enum adgs1408_chip_id { | ||
ADGS1408 = 1, | ||
ADGS1409, | ||
}; | ||
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static int adgs1408_spi_reg_write(struct spi_device *spi, | ||
u8 reg_addr, u8 reg_data) | ||
{ | ||
u8 tx_buf[2]; | ||
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tx_buf[0] = reg_addr; | ||
tx_buf[1] = reg_data; | ||
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return spi_write_then_read(spi, tx_buf, sizeof(tx_buf), NULL, 0); | ||
} | ||
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static int adgs1408_set(struct mux_control *mux, int state) | ||
{ | ||
struct spi_device *spi = to_spi_device(mux->chip->dev.parent); | ||
u8 reg; | ||
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if (state == MUX_IDLE_DISCONNECT) | ||
reg = ADGS1408_DISABLE; | ||
else | ||
reg = ADGS1408_MUX(state); | ||
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return adgs1408_spi_reg_write(spi, ADGS1408_SW_DATA, reg); | ||
} | ||
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static const struct mux_control_ops adgs1408_ops = { | ||
.set = adgs1408_set, | ||
}; | ||
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static int adgs1408_probe(struct spi_device *spi) | ||
{ | ||
struct device *dev = &spi->dev; | ||
enum adgs1408_chip_id chip_id; | ||
struct mux_chip *mux_chip; | ||
struct mux_control *mux; | ||
s32 idle_state; | ||
int ret; | ||
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chip_id = (enum adgs1408_chip_id)of_device_get_match_data(dev); | ||
if (!chip_id) | ||
chip_id = spi_get_device_id(spi)->driver_data; | ||
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mux_chip = devm_mux_chip_alloc(dev, 1, 0); | ||
if (IS_ERR(mux_chip)) | ||
return PTR_ERR(mux_chip); | ||
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mux_chip->ops = &adgs1408_ops; | ||
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ret = adgs1408_spi_reg_write(spi, ADGS1408_SW_DATA, ADGS1408_DISABLE); | ||
if (ret < 0) | ||
return ret; | ||
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ret = device_property_read_u32(dev, "idle-state", (u32 *)&idle_state); | ||
if (ret < 0) | ||
idle_state = MUX_IDLE_AS_IS; | ||
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mux = mux_chip->mux; | ||
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if (chip_id == ADGS1408) | ||
mux->states = 8; | ||
else | ||
mux->states = 4; | ||
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switch (idle_state) { | ||
case MUX_IDLE_DISCONNECT: | ||
case MUX_IDLE_AS_IS: | ||
case 0 ... 7: | ||
/* adgs1409 supports only 4 states */ | ||
if (idle_state < mux->states) { | ||
mux->idle_state = idle_state; | ||
break; | ||
} | ||
/* fall through */ | ||
default: | ||
dev_err(dev, "invalid idle-state %d\n", idle_state); | ||
return -EINVAL; | ||
} | ||
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return devm_mux_chip_register(dev, mux_chip); | ||
} | ||
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static const struct spi_device_id adgs1408_spi_id[] = { | ||
{ "adgs1408", ADGS1408 }, | ||
{ "adgs1409", ADGS1409 }, | ||
{ } | ||
}; | ||
MODULE_DEVICE_TABLE(spi, adgs1408_spi_id); | ||
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static const struct of_device_id adgs1408_of_match[] = { | ||
{ .compatible = "adi,adgs1408", .data = (void *)ADGS1408, }, | ||
{ .compatible = "adi,adgs1409", .data = (void *)ADGS1409, }, | ||
{ } | ||
}; | ||
MODULE_DEVICE_TABLE(of, adgs1408_of_match); | ||
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static struct spi_driver adgs1408_driver = { | ||
.driver = { | ||
.name = "adgs1408", | ||
.of_match_table = of_match_ptr(adgs1408_of_match), | ||
}, | ||
.probe = adgs1408_probe, | ||
.id_table = adgs1408_spi_id, | ||
}; | ||
module_spi_driver(adgs1408_driver); | ||
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MODULE_AUTHOR("Mircea Caprioru <[email protected]>"); | ||
MODULE_DESCRIPTION("Analog Devices ADGS1408 MUX driver"); | ||
MODULE_LICENSE("GPL v2"); |