+// SPDX-License-Identifier: GPL-2.0+
/*
+ * Copyright (c) 2014 Google, Inc
+ *
* (C) Copyright 2002
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
*
* Influenced by code from:
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
- *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
*/
#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <log.h>
+#include <malloc.h>
#include <spi.h>
+#include <asm/gpio.h>
+#include <linux/delay.h>
-#include <malloc.h>
+DECLARE_GLOBAL_DATA_PTR;
-/*-----------------------------------------------------------------------
- * Definitions
- */
+struct soft_spi_platdata {
+ struct gpio_desc cs;
+ struct gpio_desc sclk;
+ struct gpio_desc mosi;
+ struct gpio_desc miso;
+ int spi_delay_us;
+ int flags;
+};
-#ifdef DEBUG_SPI
-#define PRINTD(fmt,args...) printf (fmt ,##args)
-#else
-#define PRINTD(fmt,args...)
-#endif
+#define SPI_MASTER_NO_RX BIT(0)
+#define SPI_MASTER_NO_TX BIT(1)
-struct soft_spi_slave {
- struct spi_slave slave;
+struct soft_spi_priv {
unsigned int mode;
};
-static inline struct soft_spi_slave *to_soft_spi(struct spi_slave *slave)
+static int soft_spi_scl(struct udevice *dev, int bit)
{
- return container_of(slave, struct soft_spi_slave, slave);
-}
-
-/*=====================================================================*/
-/* Public Functions */
-/*=====================================================================*/
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_platdata *plat = dev_get_platdata(bus);
-/*-----------------------------------------------------------------------
- * Initialization
- */
-void spi_init (void)
-{
-#ifdef SPI_INIT
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
+ dm_gpio_set_value(&plat->sclk, bit);
- SPI_INIT;
-#endif
+ return 0;
}
-struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
- unsigned int max_hz, unsigned int mode)
+static int soft_spi_sda(struct udevice *dev, int bit)
{
- struct soft_spi_slave *ss;
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_platdata *plat = dev_get_platdata(bus);
- if (!spi_cs_is_valid(bus, cs))
- return NULL;
+ dm_gpio_set_value(&plat->mosi, bit);
- ss = malloc(sizeof(struct soft_spi_slave));
- if (!ss)
- return NULL;
+ return 0;
+}
- ss->slave.bus = bus;
- ss->slave.cs = cs;
- ss->mode = mode;
+static int soft_spi_cs_activate(struct udevice *dev)
+{
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_platdata *plat = dev_get_platdata(bus);
- /* TODO: Use max_hz to limit the SCK rate */
+ dm_gpio_set_value(&plat->cs, 0);
+ dm_gpio_set_value(&plat->sclk, 0);
+ dm_gpio_set_value(&plat->cs, 1);
- return &ss->slave;
+ return 0;
}
-void spi_free_slave(struct spi_slave *slave)
+static int soft_spi_cs_deactivate(struct udevice *dev)
{
- struct soft_spi_slave *ss = to_soft_spi(slave);
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_platdata *plat = dev_get_platdata(bus);
+
+ dm_gpio_set_value(&plat->cs, 0);
- free(ss);
+ return 0;
}
-int spi_claim_bus(struct spi_slave *slave)
+static int soft_spi_claim_bus(struct udevice *dev)
{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
-
/*
* Make sure the SPI clock is in idle state as defined for
* this slave.
*/
- if (ss->mode & SPI_CPOL)
- SPI_SCL(1);
- else
- SPI_SCL(0);
-
- return 0;
+ return soft_spi_scl(dev, 0);
}
-void spi_release_bus(struct spi_slave *slave)
+static int soft_spi_release_bus(struct udevice *dev)
{
/* Nothing to do */
+ return 0;
}
/*-----------------------------------------------------------------------
* input data overwrites the output data (since both are buffered by
* temporary variables, this is OK).
*/
-int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
- const void *dout, void *din, unsigned long flags)
+static int soft_spi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
+ struct udevice *bus = dev_get_parent(dev);
+ struct soft_spi_priv *priv = dev_get_priv(bus);
+ struct soft_spi_platdata *plat = dev_get_platdata(bus);
uchar tmpdin = 0;
uchar tmpdout = 0;
const u8 *txd = dout;
u8 *rxd = din;
- int cpol = ss->mode & SPI_CPOL;
- int cpha = ss->mode & SPI_CPHA;
+ int cpha = priv->mode & SPI_CPHA;
unsigned int j;
- PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
- slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);
+ debug("spi_xfer: slave %s:%s dout %08X din %08X bitlen %u\n",
+ dev->parent->name, dev->name, *(uint *)txd, *(uint *)rxd,
+ bitlen);
if (flags & SPI_XFER_BEGIN)
- spi_cs_activate(slave);
+ soft_spi_cs_activate(dev);
- for(j = 0; j < bitlen; j++) {
+ for (j = 0; j < bitlen; j++) {
/*
* Check if it is time to work on a new byte.
*/
- if((j % 8) == 0) {
- tmpdout = *txd++;
- if(j != 0) {
- *rxd++ = tmpdin;
+ if ((j % 8) == 0) {
+ if (txd)
+ tmpdout = *txd++;
+ else
+ tmpdout = 0;
+ if (j != 0) {
+ if (rxd)
+ *rxd++ = tmpdin;
}
tmpdin = 0;
}
if (!cpha)
- SPI_SCL(!cpol);
- SPI_SDA(tmpdout & 0x80);
- SPI_DELAY;
+ soft_spi_scl(dev, 0);
+ if ((plat->flags & SPI_MASTER_NO_TX) == 0)
+ soft_spi_sda(dev, !!(tmpdout & 0x80));
+ udelay(plat->spi_delay_us);
if (cpha)
- SPI_SCL(!cpol);
+ soft_spi_scl(dev, 0);
else
- SPI_SCL(cpol);
+ soft_spi_scl(dev, 1);
tmpdin <<= 1;
- tmpdin |= SPI_READ;
+ if ((plat->flags & SPI_MASTER_NO_RX) == 0)
+ tmpdin |= dm_gpio_get_value(&plat->miso);
tmpdout <<= 1;
- SPI_DELAY;
+ udelay(plat->spi_delay_us);
if (cpha)
- SPI_SCL(cpol);
+ soft_spi_scl(dev, 1);
}
/*
* If the number of bits isn't a multiple of 8, shift the last
* bits over to left-justify them. Then store the last byte
* read in.
*/
- if((bitlen % 8) != 0)
- tmpdin <<= 8 - (bitlen % 8);
- *rxd++ = tmpdin;
+ if (rxd) {
+ if ((bitlen % 8) != 0)
+ tmpdin <<= 8 - (bitlen % 8);
+ *rxd++ = tmpdin;
+ }
if (flags & SPI_XFER_END)
- spi_cs_deactivate(slave);
+ soft_spi_cs_deactivate(dev);
+
+ return 0;
+}
- return(0);
+static int soft_spi_set_speed(struct udevice *dev, unsigned int speed)
+{
+ /* Accept any speed */
+ return 0;
+}
+
+static int soft_spi_set_mode(struct udevice *dev, unsigned int mode)
+{
+ struct soft_spi_priv *priv = dev_get_priv(dev);
+
+ priv->mode = mode;
+
+ return 0;
+}
+
+static const struct dm_spi_ops soft_spi_ops = {
+ .claim_bus = soft_spi_claim_bus,
+ .release_bus = soft_spi_release_bus,
+ .xfer = soft_spi_xfer,
+ .set_speed = soft_spi_set_speed,
+ .set_mode = soft_spi_set_mode,
+};
+
+static int soft_spi_ofdata_to_platdata(struct udevice *dev)
+{
+ struct soft_spi_platdata *plat = dev->platdata;
+ const void *blob = gd->fdt_blob;
+ int node = dev_of_offset(dev);
+
+ plat->spi_delay_us = fdtdec_get_int(blob, node, "spi-delay-us", 0);
+
+ return 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;
+ 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;
+
+ if (gpio_request_by_name(dev, "cs-gpios", 0, &plat->cs,
+ GPIOD_IS_OUT | cs_flags) ||
+ 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 = "spi-gpio" },
+ { }
+};
+
+U_BOOT_DRIVER(soft_spi) = {
+ .name = "soft_spi",
+ .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),
+ .probe = soft_spi_probe,
+};
projects / oweals / u-boot.git / blobdiff