linux-zen-server/drivers/mfd/at91-usart.c

69 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Driver for AT91 USART
*
* Copyright (C) 2018 Microchip Technology
*
* Author: Radu Pirea <radu.pirea@microchip.com>
*
*/
#include <dt-bindings/mfd/at91-usart.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/of.h>
#include <linux/property.h>
static const struct mfd_cell at91_usart_spi_subdev =
MFD_CELL_NAME("at91_usart_spi");
static const struct mfd_cell at91_usart_serial_subdev =
MFD_CELL_NAME("atmel_usart_serial");
static int at91_usart_mode_probe(struct platform_device *pdev)
{
const struct mfd_cell *cell;
u32 opmode = AT91_USART_MODE_SERIAL;
device_property_read_u32(&pdev->dev, "atmel,usart-mode", &opmode);
switch (opmode) {
case AT91_USART_MODE_SPI:
cell = &at91_usart_spi_subdev;
break;
case AT91_USART_MODE_SERIAL:
cell = &at91_usart_serial_subdev;
break;
default:
dev_err(&pdev->dev, "atmel,usart-mode has an invalid value %u\n",
opmode);
return -EINVAL;
}
return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, cell, 1,
NULL, 0, NULL);
}
static const struct of_device_id at91_usart_mode_of_match[] = {
{ .compatible = "atmel,at91rm9200-usart" },
{ .compatible = "atmel,at91sam9260-usart" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, at91_usart_mode_of_match);
static struct platform_driver at91_usart_mfd = {
.probe = at91_usart_mode_probe,
.driver = {
.name = "at91_usart_mode",
.of_match_table = at91_usart_mode_of_match,
},
};
module_platform_driver(at91_usart_mfd);
MODULE_AUTHOR("Radu Pirea <radu.pirea@microchip.com>");
MODULE_DESCRIPTION("AT91 USART MFD driver");
MODULE_LICENSE("GPL v2");