u-boot/drivers/spi/altera_spi.c
Simon Glass 8b85dfc675 dm: Avoid accessing seq directly
At present various drivers etc. access the device's 'seq' member directly.
This makes it harder to change the meaning of that member. Change access
to go through a function instead.

The drivers/i2c/lpc32xx_i2c.c file is left unchanged for now.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-12-18 20:32:21 -07:00

209 lines
4.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Altera SPI driver
*
* based on bfin_spi.c
* Copyright (c) 2005-2008 Analog Devices Inc.
* Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <log.h>
#include <malloc.h>
#include <fdtdec.h>
#include <spi.h>
#include <asm/io.h>
#include <linux/bitops.h>
#define ALTERA_SPI_STATUS_RRDY_MSK BIT(7)
#define ALTERA_SPI_CONTROL_SSO_MSK BIT(10)
#ifndef CONFIG_ALTERA_SPI_IDLE_VAL
#define CONFIG_ALTERA_SPI_IDLE_VAL 0xff
#endif
struct altera_spi_regs {
u32 rxdata;
u32 txdata;
u32 status;
u32 control;
u32 _reserved;
u32 slave_sel;
};
struct altera_spi_plat {
struct altera_spi_regs *regs;
};
struct altera_spi_priv {
struct altera_spi_regs *regs;
};
static void spi_cs_activate(struct udevice *dev, uint cs)
{
struct udevice *bus = dev->parent;
struct altera_spi_priv *priv = dev_get_priv(bus);
struct altera_spi_regs *const regs = priv->regs;
writel(1 << cs, &regs->slave_sel);
writel(ALTERA_SPI_CONTROL_SSO_MSK, &regs->control);
}
static void spi_cs_deactivate(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct altera_spi_priv *priv = dev_get_priv(bus);
struct altera_spi_regs *const regs = priv->regs;
writel(0, &regs->control);
writel(0, &regs->slave_sel);
}
static int altera_spi_claim_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct altera_spi_priv *priv = dev_get_priv(bus);
struct altera_spi_regs *const regs = priv->regs;
writel(0, &regs->control);
writel(0, &regs->slave_sel);
return 0;
}
static int altera_spi_release_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct altera_spi_priv *priv = dev_get_priv(bus);
struct altera_spi_regs *const regs = priv->regs;
writel(0, &regs->slave_sel);
return 0;
}
static int altera_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *bus = dev->parent;
struct altera_spi_priv *priv = dev_get_priv(bus);
struct altera_spi_regs *const regs = priv->regs;
struct dm_spi_slave_plat *slave_plat = dev_get_parent_plat(dev);
/* assume spi core configured to do 8 bit transfers */
unsigned int bytes = bitlen / 8;
const unsigned char *txp = dout;
unsigned char *rxp = din;
uint32_t reg, data, start;
debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__,
dev_seq(bus), slave_plat->cs, bitlen, bytes, flags);
if (bitlen == 0)
goto done;
if (bitlen % 8) {
flags |= SPI_XFER_END;
goto done;
}
/* empty read buffer */
if (readl(&regs->status) & ALTERA_SPI_STATUS_RRDY_MSK)
readl(&regs->rxdata);
if (flags & SPI_XFER_BEGIN)
spi_cs_activate(dev, slave_plat->cs);
while (bytes--) {
if (txp)
data = *txp++;
else
data = CONFIG_ALTERA_SPI_IDLE_VAL;
debug("%s: tx:%x ", __func__, data);
writel(data, &regs->txdata);
start = get_timer(0);
while (1) {
reg = readl(&regs->status);
if (reg & ALTERA_SPI_STATUS_RRDY_MSK)
break;
if (get_timer(start) > (CONFIG_SYS_HZ / 1000)) {
debug("%s: Transmission timed out!\n", __func__);
return -1;
}
}
data = readl(&regs->rxdata);
if (rxp)
*rxp++ = data & 0xff;
debug("rx:%x\n", data);
}
done:
if (flags & SPI_XFER_END)
spi_cs_deactivate(dev);
return 0;
}
static int altera_spi_set_speed(struct udevice *bus, uint speed)
{
return 0;
}
static int altera_spi_set_mode(struct udevice *bus, uint mode)
{
return 0;
}
static int altera_spi_probe(struct udevice *bus)
{
struct altera_spi_plat *plat = dev_get_plat(bus);
struct altera_spi_priv *priv = dev_get_priv(bus);
priv->regs = plat->regs;
return 0;
}
static int altera_spi_of_to_plat(struct udevice *bus)
{
struct altera_spi_plat *plat = dev_get_plat(bus);
plat->regs = map_physmem(dev_read_addr(bus),
sizeof(struct altera_spi_regs),
MAP_NOCACHE);
return 0;
}
static const struct dm_spi_ops altera_spi_ops = {
.claim_bus = altera_spi_claim_bus,
.release_bus = altera_spi_release_bus,
.xfer = altera_spi_xfer,
.set_speed = altera_spi_set_speed,
.set_mode = altera_spi_set_mode,
/*
* cs_info is not needed, since we require all chip selects to be
* in the device tree explicitly
*/
};
static const struct udevice_id altera_spi_ids[] = {
{ .compatible = "altr,spi-1.0" },
{}
};
U_BOOT_DRIVER(altera_spi) = {
.name = "altera_spi",
.id = UCLASS_SPI,
.of_match = altera_spi_ids,
.ops = &altera_spi_ops,
.of_to_plat = altera_spi_of_to_plat,
.plat_auto = sizeof(struct altera_spi_plat),
.priv_auto = sizeof(struct altera_spi_priv),
.probe = altera_spi_probe,
};