+// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2014 Google, Inc
*
*
* Influenced by code from:
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
- *
- * SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
+#include <log.h>
#include <malloc.h>
#include <spi.h>
+#include <asm/global_data.h>
#include <asm/gpio.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
DECLARE_GLOBAL_DATA_PTR;
-struct soft_spi_platdata {
+struct soft_spi_plat {
struct gpio_desc cs;
struct gpio_desc sclk;
struct gpio_desc mosi;
struct gpio_desc miso;
int spi_delay_us;
+ int flags;
};
+#define SPI_MASTER_NO_RX BIT(0)
+#define SPI_MASTER_NO_TX BIT(1)
+
struct soft_spi_priv {
unsigned int mode;
};
static int soft_spi_scl(struct udevice *dev, int bit)
{
- struct soft_spi_platdata *plat = dev->platdata;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_plat *plat = dev_get_plat(bus);
dm_gpio_set_value(&plat->sclk, bit);
static int soft_spi_sda(struct udevice *dev, int bit)
{
- struct soft_spi_platdata *plat = dev->platdata;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_plat *plat = dev_get_plat(bus);
dm_gpio_set_value(&plat->mosi, bit);
static int soft_spi_cs_activate(struct udevice *dev)
{
- struct soft_spi_platdata *plat = dev->platdata;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_priv *priv = dev_get_priv(bus);
+ struct soft_spi_plat *plat = dev_get_plat(bus);
+ int cidle = !!(priv->mode & SPI_CPOL);
dm_gpio_set_value(&plat->cs, 0);
- dm_gpio_set_value(&plat->sclk, 0);
+ dm_gpio_set_value(&plat->sclk, cidle); /* to idle */
dm_gpio_set_value(&plat->cs, 1);
return 0;
static int soft_spi_cs_deactivate(struct udevice *dev)
{
- struct soft_spi_platdata *plat = dev->platdata;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_plat *plat = dev_get_plat(bus);
dm_gpio_set_value(&plat->cs, 0);
static int soft_spi_claim_bus(struct udevice *dev)
{
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_priv *priv = dev_get_priv(bus);
+ int cidle = !!(priv->mode & SPI_CPOL);
/*
* Make sure the SPI clock is in idle state as defined for
* this slave.
*/
- return soft_spi_scl(dev, 0);
+ return soft_spi_scl(dev, cidle);
}
static int soft_spi_release_bus(struct udevice *dev)
static int soft_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
- struct soft_spi_priv *priv = dev_get_priv(dev);
- struct soft_spi_platdata *plat = dev->platdata;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_priv *priv = dev_get_priv(bus);
+ struct soft_spi_plat *plat = dev_get_plat(bus);
uchar tmpdin = 0;
uchar tmpdout = 0;
const u8 *txd = dout;
u8 *rxd = din;
- int cpha = priv->mode & SPI_CPHA;
+ int cpha = !!(priv->mode & SPI_CPHA);
+ int cidle = !!(priv->mode & SPI_CPOL);
unsigned int j;
debug("spi_xfer: slave %s:%s dout %08X din %08X bitlen %u\n",
tmpdin = 0;
}
- if (!cpha)
- soft_spi_scl(dev, 0);
- soft_spi_sda(dev, tmpdout & 0x80);
- udelay(plat->spi_delay_us);
+ /*
+ * CPOL 0: idle is low (0), active is high (1)
+ * CPOL 1: idle is high (1), active is low (0)
+ */
+
+ /*
+ * drive bit
+ * CPHA 1: CLK from idle to active
+ */
if (cpha)
- soft_spi_scl(dev, 0);
+ soft_spi_scl(dev, !cidle);
+ if ((plat->flags & SPI_MASTER_NO_TX) == 0)
+ soft_spi_sda(dev, !!(tmpdout & 0x80));
+ udelay(plat->spi_delay_us);
+
+ /*
+ * sample bit
+ * CPHA 0: CLK from idle to active
+ * CPHA 1: CLK from active to idle
+ */
+ if (!cpha)
+ soft_spi_scl(dev, !cidle);
else
- soft_spi_scl(dev, 1);
+ soft_spi_scl(dev, cidle);
tmpdin <<= 1;
- tmpdin |= dm_gpio_get_value(&plat->miso);
+ if ((plat->flags & SPI_MASTER_NO_RX) == 0)
+ tmpdin |= dm_gpio_get_value(&plat->miso);
tmpdout <<= 1;
udelay(plat->spi_delay_us);
- if (cpha)
- soft_spi_scl(dev, 1);
+
+ /*
+ * drive bit
+ * CPHA 0: CLK from active to idle
+ */
+ if (!cpha)
+ soft_spi_scl(dev, cidle);
}
/*
* If the number of bits isn't a multiple of 8, shift the last
static int soft_spi_set_speed(struct udevice *dev, unsigned int speed)
{
- /* Accept any speed */
+ /* Ignore any speed settings. Speed is implemented via "spi-delay-us" */
return 0;
}
.set_mode = soft_spi_set_mode,
};
-static int soft_spi_ofdata_to_platdata(struct udevice *dev)
+static int soft_spi_of_to_plat(struct udevice *dev)
{
- struct soft_spi_platdata *plat = dev->platdata;
+ struct soft_spi_plat *plat = dev_get_plat(dev);
const void *blob = gd->fdt_blob;
- int node = dev->of_offset;
+ int node = dev_of_offset(dev);
plat->spi_delay_us = fdtdec_get_int(blob, node, "spi-delay-us", 0);
static int soft_spi_probe(struct udevice *dev)
{
struct spi_slave *slave = dev_get_parent_priv(dev);
- struct soft_spi_platdata *plat = dev->platdata;
+ struct soft_spi_plat *plat = dev_get_plat(dev);
int cs_flags, clk_flags;
+ int ret;
+
+ cs_flags = (slave && slave->mode & SPI_CS_HIGH) ? 0 : GPIOD_ACTIVE_LOW;
+ clk_flags = (slave && slave->mode & SPI_CPOL) ? GPIOD_ACTIVE_LOW : 0;
- cs_flags = (slave->mode & SPI_CS_HIGH) ? 0 : GPIOD_ACTIVE_LOW;
- clk_flags = (slave->mode & SPI_CPOL) ? GPIOD_ACTIVE_LOW : 0;
- if (gpio_request_by_name(dev, "cs-gpio", 0, &plat->cs,
+ if (gpio_request_by_name(dev, "cs-gpios", 0, &plat->cs,
GPIOD_IS_OUT | cs_flags) ||
- gpio_request_by_name(dev, "sclk-gpio", 0, &plat->sclk,
- GPIOD_IS_OUT | clk_flags) ||
- gpio_request_by_name(dev, "mosi-gpio", 0, &plat->mosi,
- GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE) ||
- gpio_request_by_name(dev, "miso-gpio", 0, &plat->miso,
- GPIOD_IS_IN))
+ gpio_request_by_name(dev, "gpio-sck", 0, &plat->sclk,
+ GPIOD_IS_OUT | clk_flags))
+ return -EINVAL;
+
+ ret = gpio_request_by_name(dev, "gpio-mosi", 0, &plat->mosi,
+ GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
+ if (ret)
+ plat->flags |= SPI_MASTER_NO_TX;
+
+ ret = gpio_request_by_name(dev, "gpio-miso", 0, &plat->miso,
+ GPIOD_IS_IN);
+ if (ret)
+ plat->flags |= SPI_MASTER_NO_RX;
+
+ if ((plat->flags & (SPI_MASTER_NO_RX | SPI_MASTER_NO_TX)) ==
+ (SPI_MASTER_NO_RX | SPI_MASTER_NO_TX))
return -EINVAL;
return 0;
}
static const struct udevice_id soft_spi_ids[] = {
- { .compatible = "u-boot,soft-spi" },
+ { .compatible = "spi-gpio" },
{ }
};
.id = UCLASS_SPI,
.of_match = soft_spi_ids,
.ops = &soft_spi_ops,
- .ofdata_to_platdata = soft_spi_ofdata_to_platdata,
- .platdata_auto_alloc_size = sizeof(struct soft_spi_platdata),
- .priv_auto_alloc_size = sizeof(struct soft_spi_priv),
+ .of_to_plat = soft_spi_of_to_plat,
+ .plat_auto = sizeof(struct soft_spi_plat),
+ .priv_auto = sizeof(struct soft_spi_priv),
.probe = soft_spi_probe,
};
projects / platform / kernel / u-boot.git / blobdiff