diff options
Diffstat (limited to 'drivers/spi/spi-uclass.c')
-rw-r--r-- | drivers/spi/spi-uclass.c | 390 |
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, +}; |