u-boot/drivers/misc/microchip_flexcom.c
Eugen Hristev f81649586d misc: microchip_flexcom: introduce microchip_flexcom driver
The Microchip Flexcom is just a wrapper which embeds a SPI controller,
an I2C controller and an USART.
Only one function can be used at a time and is chosen at boot time according
to the device tree.
The bindings are kept as in Linux.
The driver registers to MISC_UCLASS.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
2019-10-24 13:01:57 +03:00

64 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2019, Microchip Technology, Inc.
* Author: Eugen Hristev <eugen.hristev@microchip.com>
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <misc.h>
#include <asm/io.h>
struct microchip_flexcom_regs {
u32 cr;
};
struct microchip_flexcom_platdata {
struct microchip_flexcom_regs *regs;
u32 flexcom_mode;
};
static int microchip_flexcom_ofdata_to_platdata(struct udevice *dev)
{
struct microchip_flexcom_platdata *plat = dev_get_platdata(dev);
int ret;
plat->regs = map_physmem(devfdt_get_addr(dev),
sizeof(struct microchip_flexcom_regs),
MAP_NOCACHE);
ret = dev_read_u32(dev, "atmel,flexcom-mode", &plat->flexcom_mode);
if (IS_ERR_VALUE(ret)) {
debug("Missing atmel,flexcom-mode property\n");
return ret;
}
/*
* The mode must have only 2 bits. If any other bits are set,
* the value is not supported.
*/
if (plat->flexcom_mode & 0xfffffffc) {
debug("Wrong atmel,flexcom-mode property\n");
return -EINVAL;
}
writel(plat->flexcom_mode, &plat->regs->cr);
return 0;
}
static const struct udevice_id microchip_flexcom_ids[] = {
{ .compatible = "atmel,sama5d2-flexcom" },
{ .compatible = "microchip,flexcom" },
{}
};
U_BOOT_DRIVER(microchip_flexcom) = {
.name = "microchip_flexcom",
.id = UCLASS_MISC,
.of_match = microchip_flexcom_ids,
.ofdata_to_platdata = microchip_flexcom_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct microchip_flexcom_platdata),
};