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path: root/drivers/spi/spi-uclass.c
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Diffstat (limited to 'drivers/spi/spi-uclass.c')
-rw-r--r--drivers/spi/spi-uclass.c390
1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
new file mode 100644
index 0000000..13c6b77
--- /dev/null
+++ b/drivers/spi/spi-uclass.c
@@ -0,0 +1,390 @@
+/*
+ * Copyright (c) 2014 Google, Inc
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <malloc.h>
+#include <spi.h>
+#include <dm/device-internal.h>
+#include <dm/uclass-internal.h>
+#include <dm/root.h>
+#include <dm/lists.h>
+#include <dm/util.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
+{
+ struct dm_spi_ops *ops;
+ int ret;
+
+ ops = spi_get_ops(bus);
+ if (ops->set_speed)
+ ret = ops->set_speed(bus, speed);
+ else
+ ret = -EINVAL;
+ if (ret) {
+ printf("Cannot set speed (err=%d)\n", ret);
+ return ret;
+ }
+
+ if (ops->set_mode)
+ ret = ops->set_mode(bus, mode);
+ else
+ ret = -EINVAL;
+ if (ret) {
+ printf("Cannot set mode (err=%d)\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ struct udevice *dev = slave->dev;
+ struct udevice *bus = dev->parent;
+ struct dm_spi_ops *ops = spi_get_ops(bus);
+ struct dm_spi_bus *spi = bus->uclass_priv;
+ int speed;
+ int ret;
+
+ speed = slave->max_hz;
+ if (spi->max_hz) {
+ if (speed)
+ speed = min(speed, spi->max_hz);
+ else
+ speed = spi->max_hz;
+ }
+ if (!speed)
+ speed = 100000;
+ ret = spi_set_speed_mode(bus, speed, slave->mode);
+ if (ret)
+ return ret;
+
+ return ops->claim_bus ? ops->claim_bus(bus) : 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+ struct udevice *dev = slave->dev;
+ struct udevice *bus = dev->parent;
+ struct dm_spi_ops *ops = spi_get_ops(bus);
+
+ if (ops->release_bus)
+ ops->release_bus(bus);
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct udevice *dev = slave->dev;
+ struct udevice *bus = dev->parent;
+
+ if (bus->uclass->uc_drv->id != UCLASS_SPI)
+ return -EOPNOTSUPP;
+
+ return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
+}
+
+int spi_post_bind(struct udevice *dev)
+{
+ /* Scan the bus for devices */
+ return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+int spi_post_probe(struct udevice *dev)
+{
+ struct dm_spi_bus *spi = dev->uclass_priv;
+
+ spi->max_hz = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+ "spi-max-frequency", 0);
+
+ return 0;
+}
+
+int spi_chip_select(struct udevice *dev)
+{
+ struct spi_slave *slave = dev_get_parentdata(dev);
+
+ return slave ? slave->cs : -ENOENT;
+}
+
+/**
+ * spi_find_chip_select() - Find the slave attached to chip select
+ *
+ * @bus: SPI bus to search
+ * @cs: Chip select to look for
+ * @devp: Returns the slave device if found
+ * @return 0 if found, -ENODEV on error
+ */
+static int spi_find_chip_select(struct udevice *bus, int cs,
+ struct udevice **devp)
+{
+ struct udevice *dev;
+
+ for (device_find_first_child(bus, &dev); dev;
+ device_find_next_child(&dev)) {
+ struct spi_slave store;
+ struct spi_slave *slave = dev_get_parentdata(dev);
+
+ if (!slave) {
+ slave = &store;
+ spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
+ slave);
+ }
+ debug("%s: slave=%p, cs=%d\n", __func__, slave,
+ slave ? slave->cs : -1);
+ if (slave && slave->cs == cs) {
+ *devp = dev;
+ return 0;
+ }
+ }
+
+ return -ENODEV;
+}
+
+int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
+{
+ struct spi_cs_info info;
+ struct udevice *bus;
+ int ret;
+
+ ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
+ if (ret) {
+ debug("%s: No bus %d\n", __func__, busnum);
+ return ret;
+ }
+
+ return spi_cs_info(bus, cs, &info);
+}
+
+int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
+{
+ struct spi_cs_info local_info;
+ struct dm_spi_ops *ops;
+ int ret;
+
+ if (!info)
+ info = &local_info;
+
+ /* If there is a device attached, return it */
+ info->dev = NULL;
+ ret = spi_find_chip_select(bus, cs, &info->dev);
+ if (!ret)
+ return 0;
+
+ /*
+ * Otherwise ask the driver. For the moment we don't have CS info.
+ * When we do we could provide the driver with a helper function
+ * to figure out what chip selects are valid, or just handle the
+ * request.
+ */
+ ops = spi_get_ops(bus);
+ if (ops->cs_info)
+ return ops->cs_info(bus, cs, info);
+
+ /*
+ * We could assume there is at least one valid chip select, but best
+ * to be sure and return an error in this case. The driver didn't
+ * care enough to tell us.
+ */
+ return -ENODEV;
+}
+
+int spi_bind_device(struct udevice *bus, int cs, const char *drv_name,
+ const char *dev_name, struct udevice **devp)
+{
+ struct driver *drv;
+ int ret;
+
+ drv = lists_driver_lookup_name(drv_name);
+ if (!drv) {
+ printf("Cannot find driver '%s'\n", drv_name);
+ return -ENOENT;
+ }
+ ret = device_bind(bus, drv, dev_name, NULL, -1, devp);
+ if (ret) {
+ printf("Cannot create device named '%s' (err=%d)\n",
+ dev_name, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
+ struct udevice **devp)
+{
+ struct udevice *bus, *dev;
+ int ret;
+
+ ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
+ if (ret) {
+ debug("%s: No bus %d\n", __func__, busnum);
+ return ret;
+ }
+ ret = spi_find_chip_select(bus, cs, &dev);
+ if (ret) {
+ debug("%s: No cs %d\n", __func__, cs);
+ return ret;
+ }
+ *busp = bus;
+ *devp = dev;
+
+ return ret;
+}
+
+int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
+ const char *drv_name, const char *dev_name,
+ struct udevice **busp, struct spi_slave **devp)
+{
+ struct udevice *bus, *dev;
+ struct spi_slave *slave;
+ bool created = false;
+ int ret;
+
+ ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
+ if (ret) {
+ printf("Invalid bus %d (err=%d)\n", busnum, ret);
+ return ret;
+ }
+ ret = spi_find_chip_select(bus, cs, &dev);
+
+ /*
+ * If there is no such device, create one automatically. This means
+ * that we don't need a device tree node or platform data for the
+ * SPI flash chip - we will bind to the correct driver.
+ */
+ if (ret == -ENODEV && drv_name) {
+ debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
+ __func__, dev_name, busnum, cs, drv_name);
+ ret = spi_bind_device(bus, cs, drv_name, dev_name, &dev);
+ if (ret)
+ return ret;
+ created = true;
+ } else if (ret) {
+ printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
+ ret);
+ return ret;
+ }
+
+ if (!device_active(dev)) {
+ slave = (struct spi_slave *)calloc(1,
+ sizeof(struct spi_slave));
+ if (!slave) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
+ slave);
+ if (ret)
+ goto err;
+ slave->cs = cs;
+ slave->dev = dev;
+ ret = device_probe_child(dev, slave);
+ free(slave);
+ if (ret)
+ goto err;
+ }
+
+ ret = spi_set_speed_mode(bus, speed, mode);
+ if (ret)
+ goto err;
+
+ *busp = bus;
+ *devp = dev_get_parentdata(dev);
+ debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
+
+ return 0;
+
+err:
+ if (created) {
+ device_remove(dev);
+ device_unbind(dev);
+ }
+
+ return ret;
+}
+
+/* Compatibility function - to be removed */
+struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
+ int bus_node)
+{
+ struct udevice *bus, *dev;
+ int ret;
+
+ ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
+ if (ret)
+ return NULL;
+ ret = device_get_child_by_of_offset(bus, node, &dev);
+ if (ret)
+ return NULL;
+ return dev_get_parentdata(dev);
+}
+
+/* Compatibility function - to be removed */
+struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
+ unsigned int speed, unsigned int mode)
+{
+ struct spi_slave *slave;
+ struct udevice *dev;
+ int ret;
+
+ ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
+ &slave);
+ if (ret)
+ return NULL;
+
+ return slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ device_remove(slave->dev);
+ slave->dev = NULL;
+}
+
+int spi_ofdata_to_platdata(const void *blob, int node,
+ struct spi_slave *spi)
+{
+ int mode = 0;
+
+ spi->cs = fdtdec_get_int(blob, node, "reg", -1);
+ spi->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
+ if (fdtdec_get_bool(blob, node, "spi-cpol"))
+ mode |= SPI_CPOL;
+ if (fdtdec_get_bool(blob, node, "spi-cpha"))
+ mode |= SPI_CPHA;
+ if (fdtdec_get_bool(blob, node, "spi-cs-high"))
+ mode |= SPI_CS_HIGH;
+ if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
+ mode |= SPI_PREAMBLE;
+ spi->mode = mode;
+
+ return 0;
+}
+
+UCLASS_DRIVER(spi) = {
+ .id = UCLASS_SPI,
+ .name = "spi",
+ .post_bind = spi_post_bind,
+ .post_probe = spi_post_probe,
+ .per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
+};
+
+UCLASS_DRIVER(spi_generic) = {
+ .id = UCLASS_SPI_GENERIC,
+ .name = "spi_generic",
+};
+
+U_BOOT_DRIVER(spi_generic_drv) = {
+ .name = "spi_generic_drv",
+ .id = UCLASS_SPI_GENERIC,
+};