From 4ad1e5b5d1dde19f09e728ba8b5164968f9dabeb Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Fri, 3 Aug 2012 17:26:14 +0200 Subject: spi/mxs: Add SSP/SPI device tree documentation Signed-off-by: Marek Vasut Acked-by: Chris Ball Acked-by: Shawn Guo Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/mxs-spi.txt | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) create mode 100644 Documentation/devicetree/bindings/spi/mxs-spi.txt (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/mxs-spi.txt b/Documentation/devicetree/bindings/spi/mxs-spi.txt new file mode 100644 index 00000000000..c36296f5ad2 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/mxs-spi.txt @@ -0,0 +1,18 @@ +* Freescale MX233/MX28 SSP/SPI + +Required properties: +- compatible: Should be "fsl,-spi", where soc is "imx23" or "imx28" +- reg: Offset and length of the register set for the device +- interrupts: Should contain SSP interrupts (error irq first, dma irq second) +- fsl,ssp-dma-channel: APBX DMA channel for the SSP + +Example: + +ssp0: ssp@80010000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "fsl,imx28-spi"; + reg = <0x80010000 0x2000>; + interrupts = <96 82>; + fsl,ssp-dma-channel = <0>; +}; -- cgit v1.2.3-70-g09d2 From 3ce8859e2e72713d3619285cab609d05c3591fc4 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Sat, 18 Aug 2012 09:06:27 -0700 Subject: spi: Master driver for NXP SC18IS602/603 This driver adds support for NXP SC18IS602/603 I2C to SPI bus bridge. Signed-off-by: Guenter Roeck Signed-off-by: Mark Brown --- .../devicetree/bindings/spi/spi-sc18is602.txt | 23 ++ Documentation/spi/spi-sc18is602 | 36 ++ drivers/spi/Kconfig | 6 + drivers/spi/Makefile | 1 + drivers/spi/spi-sc18is602.c | 364 +++++++++++++++++++++ include/linux/platform_data/sc18is602.h | 19 ++ 6 files changed, 449 insertions(+) create mode 100644 Documentation/devicetree/bindings/spi/spi-sc18is602.txt create mode 100644 Documentation/spi/spi-sc18is602 create mode 100644 drivers/spi/spi-sc18is602.c create mode 100644 include/linux/platform_data/sc18is602.h (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/spi-sc18is602.txt b/Documentation/devicetree/bindings/spi/spi-sc18is602.txt new file mode 100644 index 00000000000..02f9033270a --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-sc18is602.txt @@ -0,0 +1,23 @@ +NXP SC18IS602/SCIS603 + +Required properties: + - compatible : Should be one of + "nxp,sc18is602" + "nxp,sc18is602b" + "nxp,sc18is603" + - reg: I2C bus address + +Optional properties: + - clock-frequency : external oscillator clock frequency. If not + specified, the SC18IS602 default frequency (7372000) will be used. + +The clock-frequency property is relevant and needed only if the chip has an +external oscillator (SC18IS603). + +Example: + + sc18is603@28 { + compatible = "nxp,sc18is603"; + reg = <0x28>; + clock-frequency = <14744000>; + } diff --git a/Documentation/spi/spi-sc18is602 b/Documentation/spi/spi-sc18is602 new file mode 100644 index 00000000000..a45702865a3 --- /dev/null +++ b/Documentation/spi/spi-sc18is602 @@ -0,0 +1,36 @@ +Kernel driver spi-sc18is602 +=========================== + +Supported chips: + * NXP SI18IS602/602B/603 + Datasheet: http://www.nxp.com/documents/data_sheet/SC18IS602_602B_603.pdf + +Author: + Guenter Roeck + + +Description +----------- + +This driver provides connects a NXP SC18IS602/603 I2C-bus to SPI bridge to the +kernel's SPI core subsystem. + +The driver does not probe for supported chips, since the SI18IS602/603 does not +support Chip ID registers. You will have to instantiate the devices explicitly. +Please see Documentation/i2c/instantiating-devices for details. + + +Usage Notes +----------- + +This driver requires the I2C adapter driver to support raw I2C messages. I2C +adapter drivers which can only handle the SMBus protocol are not supported. + +The maximum SPI message size supported by SC18IS602/603 is 200 bytes. Attempts +to initiate longer transfers will fail with -EINVAL. EEPROM read operations and +similar large accesses have to be split into multiple chunks of no more than +200 bytes per SPI message (128 bytes of data per message is recommended). This +means that programs such as "cp" or "od", which automatically use large block +sizes to access a device, can not be used directly to read data from EEPROM. +Programs such as dd, where the block size can be specified, should be used +instead. diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 5f84b5563c2..920bb4d22d4 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -325,6 +325,12 @@ config SPI_S3C64XX help SPI driver for Samsung S3C64XX and newer SoCs. +config SPI_SC18IS602 + tristate "NXP SC18IS602/602B/603 I2C to SPI bridge" + depends on I2C + help + SPI driver for NXP SC18IS602/602B/603 I2C to SPI bridge. + config SPI_SH_MSIOF tristate "SuperH MSIOF SPI controller" depends on SUPERH && HAVE_CLK diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 3920dcf4c74..7559c984db7 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -51,6 +51,7 @@ obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o spi-s3c24xx-hw-y := spi-s3c24xx.o spi-s3c24xx-hw-$(CONFIG_SPI_S3C24XX_FIQ) += spi-s3c24xx-fiq.o obj-$(CONFIG_SPI_S3C64XX) += spi-s3c64xx.o +obj-$(CONFIG_SPI_SC18IS602) += spi-sc18is602.o obj-$(CONFIG_SPI_SH) += spi-sh.o obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o diff --git a/drivers/spi/spi-sc18is602.c b/drivers/spi/spi-sc18is602.c new file mode 100644 index 00000000000..dd9896423f0 --- /dev/null +++ b/drivers/spi/spi-sc18is602.c @@ -0,0 +1,364 @@ +/* + * NXP SC18IS602/603 SPI driver + * + * Copyright (C) Guenter Roeck + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +enum chips { sc18is602, sc18is602b, sc18is603 }; + +#define SC18IS602_BUFSIZ 200 +#define SC18IS602_CLOCK 7372000 + +#define SC18IS602_MODE_CPHA BIT(2) +#define SC18IS602_MODE_CPOL BIT(3) +#define SC18IS602_MODE_LSB_FIRST BIT(5) +#define SC18IS602_MODE_CLOCK_DIV_4 0x0 +#define SC18IS602_MODE_CLOCK_DIV_16 0x1 +#define SC18IS602_MODE_CLOCK_DIV_64 0x2 +#define SC18IS602_MODE_CLOCK_DIV_128 0x3 + +struct sc18is602 { + struct spi_master *master; + struct device *dev; + u8 ctrl; + u32 freq; + u32 speed; + + /* I2C data */ + struct i2c_client *client; + enum chips id; + u8 buffer[SC18IS602_BUFSIZ + 1]; + int tlen; /* Data queued for tx in buffer */ + int rindex; /* Receive data index in buffer */ +}; + +static int sc18is602_wait_ready(struct sc18is602 *hw, int len) +{ + int i, err; + int usecs = 1000000 * len / hw->speed + 1; + u8 dummy[1]; + + for (i = 0; i < 10; i++) { + err = i2c_master_recv(hw->client, dummy, 1); + if (err >= 0) + return 0; + usleep_range(usecs, usecs * 2); + } + return -ETIMEDOUT; +} + +static int sc18is602_txrx(struct sc18is602 *hw, struct spi_message *msg, + struct spi_transfer *t, bool do_transfer) +{ + unsigned int len = t->len; + int ret; + + if (hw->tlen == 0) { + /* First byte (I2C command) is chip select */ + hw->buffer[0] = 1 << msg->spi->chip_select; + hw->tlen = 1; + hw->rindex = 0; + } + /* + * We can not immediately send data to the chip, since each I2C message + * resembles a full SPI message (from CS active to CS inactive). + * Enqueue messages up to the first read or until do_transfer is true. + */ + if (t->tx_buf) { + memcpy(&hw->buffer[hw->tlen], t->tx_buf, len); + hw->tlen += len; + if (t->rx_buf) + do_transfer = true; + else + hw->rindex = hw->tlen - 1; + } else if (t->rx_buf) { + /* + * For receive-only transfers we still need to perform a dummy + * write to receive data from the SPI chip. + * Read data starts at the end of transmit data (minus 1 to + * account for CS). + */ + hw->rindex = hw->tlen - 1; + memset(&hw->buffer[hw->tlen], 0, len); + hw->tlen += len; + do_transfer = true; + } + + if (do_transfer && hw->tlen > 1) { + ret = sc18is602_wait_ready(hw, SC18IS602_BUFSIZ); + if (ret < 0) + return ret; + ret = i2c_master_send(hw->client, hw->buffer, hw->tlen); + if (ret < 0) + return ret; + if (ret != hw->tlen) + return -EIO; + + if (t->rx_buf) { + int rlen = hw->rindex + len; + + ret = sc18is602_wait_ready(hw, hw->tlen); + if (ret < 0) + return ret; + ret = i2c_master_recv(hw->client, hw->buffer, rlen); + if (ret < 0) + return ret; + if (ret != rlen) + return -EIO; + memcpy(t->rx_buf, &hw->buffer[hw->rindex], len); + } + hw->tlen = 0; + } + return len; +} + +static int sc18is602_setup_transfer(struct sc18is602 *hw, u32 hz, u8 mode) +{ + u8 ctrl = 0; + int ret; + + if (mode & SPI_CPHA) + ctrl |= SC18IS602_MODE_CPHA; + if (mode & SPI_CPOL) + ctrl |= SC18IS602_MODE_CPOL; + if (mode & SPI_LSB_FIRST) + ctrl |= SC18IS602_MODE_LSB_FIRST; + + /* Find the closest clock speed */ + if (hz >= hw->freq / 4) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_4; + hw->speed = hw->freq / 4; + } else if (hz >= hw->freq / 16) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_16; + hw->speed = hw->freq / 16; + } else if (hz >= hw->freq / 64) { + ctrl |= SC18IS602_MODE_CLOCK_DIV_64; + hw->speed = hw->freq / 64; + } else { + ctrl |= SC18IS602_MODE_CLOCK_DIV_128; + hw->speed = hw->freq / 128; + } + + /* + * Don't do anything if the control value did not change. The initial + * value of 0xff for hw->ctrl ensures that the correct mode will be set + * with the first call to this function. + */ + if (ctrl == hw->ctrl) + return 0; + + ret = i2c_smbus_write_byte_data(hw->client, 0xf0, ctrl); + if (ret < 0) + return ret; + + hw->ctrl = ctrl; + + return 0; +} + +static int sc18is602_check_transfer(struct spi_device *spi, + struct spi_transfer *t, int tlen) +{ + int bpw; + uint32_t hz; + + if (t && t->len + tlen > SC18IS602_BUFSIZ) + return -EINVAL; + + bpw = spi->bits_per_word; + if (t && t->bits_per_word) + bpw = t->bits_per_word; + if (bpw != 8) + return -EINVAL; + + hz = spi->max_speed_hz; + if (t && t->speed_hz) + hz = t->speed_hz; + if (hz == 0) + return -EINVAL; + + return 0; +} + +static int sc18is602_transfer_one(struct spi_master *master, + struct spi_message *m) +{ + struct sc18is602 *hw = spi_master_get_devdata(master); + struct spi_device *spi = m->spi; + struct spi_transfer *t; + int status = 0; + + /* SC18IS602 does not support CS2 */ + if (hw->id == sc18is602 && spi->chip_select == 2) { + status = -ENXIO; + goto error; + } + + hw->tlen = 0; + list_for_each_entry(t, &m->transfers, transfer_list) { + u32 hz = t->speed_hz ? : spi->max_speed_hz; + bool do_transfer; + + status = sc18is602_check_transfer(spi, t, hw->tlen); + if (status < 0) + break; + + status = sc18is602_setup_transfer(hw, hz, spi->mode); + if (status < 0) + break; + + do_transfer = t->cs_change || list_is_last(&t->transfer_list, + &m->transfers); + + if (t->len) { + status = sc18is602_txrx(hw, m, t, do_transfer); + if (status < 0) + break; + m->actual_length += status; + } + status = 0; + + if (t->delay_usecs) + udelay(t->delay_usecs); + } +error: + m->status = status; + spi_finalize_current_message(master); + + return status; +} + +static int sc18is602_setup(struct spi_device *spi) +{ + if (!spi->bits_per_word) + spi->bits_per_word = 8; + + if (spi->mode & ~(SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST)) + return -EINVAL; + + return sc18is602_check_transfer(spi, NULL, 0); +} + +static int sc18is602_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct device_node *np = dev->of_node; + struct sc18is602_platform_data *pdata = dev_get_platdata(dev); + struct sc18is602 *hw; + struct spi_master *master; + int error; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | + I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) + return -ENODEV; + + master = spi_alloc_master(dev, sizeof(struct sc18is602)); + if (!master) + return -ENOMEM; + + hw = spi_master_get_devdata(master); + i2c_set_clientdata(client, hw); + + hw->master = master; + hw->client = client; + hw->dev = dev; + hw->ctrl = 0xff; + + hw->id = id->driver_data; + + switch (hw->id) { + case sc18is602: + case sc18is602b: + master->num_chipselect = 4; + hw->freq = SC18IS602_CLOCK; + break; + case sc18is603: + master->num_chipselect = 2; + if (pdata) { + hw->freq = pdata->clock_frequency; + } else { + const __be32 *val; + int len; + + val = of_get_property(np, "clock-frequency", &len); + if (val && len >= sizeof(__be32)) + hw->freq = be32_to_cpup(val); + } + if (!hw->freq) + hw->freq = SC18IS602_CLOCK; + break; + } + master->bus_num = client->adapter->nr; + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST; + master->setup = sc18is602_setup; + master->transfer_one_message = sc18is602_transfer_one; + master->dev.of_node = np; + + error = spi_register_master(master); + if (error) + goto error_reg; + + return 0; + +error_reg: + spi_master_put(master); + return error; +} + +static int sc18is602_remove(struct i2c_client *client) +{ + struct sc18is602 *hw = i2c_get_clientdata(client); + struct spi_master *master = hw->master; + + spi_unregister_master(master); + + return 0; +} + +static const struct i2c_device_id sc18is602_id[] = { + { "sc18is602", sc18is602 }, + { "sc18is602b", sc18is602b }, + { "sc18is603", sc18is603 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, sc18is602_id); + +static struct i2c_driver sc18is602_driver = { + .driver = { + .name = "sc18is602", + }, + .probe = sc18is602_probe, + .remove = sc18is602_remove, + .id_table = sc18is602_id, +}; + +module_i2c_driver(sc18is602_driver); + +MODULE_DESCRIPTION("SC18IC602/603 SPI Master Driver"); +MODULE_AUTHOR("Guenter Roeck"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/platform_data/sc18is602.h b/include/linux/platform_data/sc18is602.h new file mode 100644 index 00000000000..997b0663415 --- /dev/null +++ b/include/linux/platform_data/sc18is602.h @@ -0,0 +1,19 @@ +/* + * Platform data for NXP SC18IS602/603 + * + * Copyright (C) 2012 Guenter Roeck + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * For further information, see the Documentation/spi/sc18is602 file. + */ + +/** + * struct sc18is602_platform_data - sc18is602 info + * @clock_frequency SC18IS603 oscillator frequency + */ +struct sc18is602_platform_data { + u32 clock_frequency; +}; -- cgit v1.2.3-70-g09d2 From 6d3952a7dfa80919842bbe01ac7f693d40a1eb84 Mon Sep 17 00:00:00 2001 From: Roland Stigge Date: Wed, 22 Aug 2012 15:49:18 +0200 Subject: spi/pl022: Add devicetree support This patch adds device tree support to the spi-pl022 driver. Based on the initial patch by Alexandre Pereira da Silva Signed-off-by: Roland Stigge Acked-by: Alexandre Pereira da Silva Reviewed-by: Linus Walleij Signed-off-by: Mark Brown --- .../devicetree/bindings/spi/spi_pl022.txt | 15 ++++ drivers/spi/spi-pl022.c | 79 +++++++++++++++++++--- 2 files changed, 85 insertions(+), 9 deletions(-) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/spi_pl022.txt b/Documentation/devicetree/bindings/spi/spi_pl022.txt index 306ec3ff3c0..877f832c30a 100644 --- a/Documentation/devicetree/bindings/spi/spi_pl022.txt +++ b/Documentation/devicetree/bindings/spi/spi_pl022.txt @@ -6,7 +6,22 @@ Required properties: - interrupts : Should contain SPI controller interrupt Optional properties: +- num-cs : total number of chipselects - cs-gpios : should specify GPIOs used for chipselects. The gpios will be referred to as reg = in the SPI child nodes. If unspecified, a single SPI device without a chip select can be used. +SPI slave nodes must be children of the SPI master node and can +contain the following properties. + +- pl022,interface : interface type: + 0: SPI + 1: Texas Instruments Synchronous Serial Frame Format + 2: Microwire (Half Duplex) +- pl022,com-mode : polling, interrupt or dma +- pl022,rx-level-trig : Rx FIFO watermark level +- pl022,tx-level-trig : Tx FIFO watermark level +- pl022,ctrl-len : Microwire interface: Control length +- pl022,wait-state : Microwire interface: Wait state +- pl022,duplex : Microwire interface: Full/Half duplex + diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index cf47802f00c..959f2acff2d 100644 --- a/drivers/spi/spi-pl022.c +++ b/drivers/spi/spi-pl022.c @@ -41,6 +41,7 @@ #include #include #include +#include /* * This macro is used to define some register default values. @@ -1778,12 +1779,14 @@ static const struct pl022_config_chip pl022_default_chip_info = { static int pl022_setup(struct spi_device *spi) { struct pl022_config_chip const *chip_info; + struct pl022_config_chip chip_info_dt; struct chip_data *chip; struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0}; int status = 0; struct pl022 *pl022 = spi_master_get_devdata(spi->master); unsigned int bits = spi->bits_per_word; u32 tmp; + struct device_node *np = spi->dev.of_node; if (!spi->max_speed_hz) return -EINVAL; @@ -1806,10 +1809,32 @@ static int pl022_setup(struct spi_device *spi) chip_info = spi->controller_data; if (chip_info == NULL) { - chip_info = &pl022_default_chip_info; - /* spi_board_info.controller_data not is supplied */ - dev_dbg(&spi->dev, - "using default controller_data settings\n"); + if (np) { + chip_info_dt = pl022_default_chip_info; + + chip_info_dt.hierarchy = SSP_MASTER; + of_property_read_u32(np, "pl022,interface", + &chip_info_dt.iface); + of_property_read_u32(np, "pl022,com-mode", + &chip_info_dt.com_mode); + of_property_read_u32(np, "pl022,rx-level-trig", + &chip_info_dt.rx_lev_trig); + of_property_read_u32(np, "pl022,tx-level-trig", + &chip_info_dt.tx_lev_trig); + of_property_read_u32(np, "pl022,ctrl-len", + &chip_info_dt.ctrl_len); + of_property_read_u32(np, "pl022,wait-state", + &chip_info_dt.wait_state); + of_property_read_u32(np, "pl022,duplex", + &chip_info_dt.duplex); + + chip_info = &chip_info_dt; + } else { + chip_info = &pl022_default_chip_info; + /* spi_board_info.controller_data not is supplied */ + dev_dbg(&spi->dev, + "using default controller_data settings\n"); + } } else dev_dbg(&spi->dev, "using user supplied controller_data settings\n"); @@ -2006,7 +2031,8 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) struct pl022_ssp_controller *platform_info = adev->dev.platform_data; struct spi_master *master; struct pl022 *pl022 = NULL; /*Data for this driver */ - int status = 0, i; + struct device_node *np = adev->dev.of_node; + int status = 0, i, num_cs; dev_info(&adev->dev, "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); @@ -2016,9 +2042,19 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) goto err_no_pdata; } + if (platform_info->num_chipselect) { + num_cs = platform_info->num_chipselect; + } else if (IS_ENABLED(CONFIG_OF)) { + of_property_read_u32(np, "num-cs", &num_cs); + } else { + dev_err(&adev->dev, "probe: no chip select defined\n"); + status = -ENODEV; + goto err_no_pdata; + } + /* Allocate master with space for data */ master = spi_alloc_master(dev, sizeof(struct pl022) + sizeof(int) * - platform_info->num_chipselect); + num_cs); if (master == NULL) { dev_err(&adev->dev, "probe - cannot alloc SPI master\n"); status = -ENOMEM; @@ -2038,17 +2074,41 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) * on this board */ master->bus_num = platform_info->bus_id; - master->num_chipselect = platform_info->num_chipselect; + master->num_chipselect = num_cs; master->cleanup = pl022_cleanup; master->setup = pl022_setup; master->prepare_transfer_hardware = pl022_prepare_transfer_hardware; master->transfer_one_message = pl022_transfer_one_message; master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware; master->rt = platform_info->rt; + master->dev.of_node = dev->of_node; - if (platform_info->num_chipselect && platform_info->chipselects) - for (i = 0; i < platform_info->num_chipselect; i++) + if (platform_info->num_chipselect && platform_info->chipselects) { + for (i = 0; i < num_cs; i++) pl022->chipselects[i] = platform_info->chipselects[i]; + } else if (IS_ENABLED(CONFIG_OF)) { + for (i = 0; i < num_cs; i++) { + int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) { + status = -EPROBE_DEFER; + goto err_no_gpio; + } + + pl022->chipselects[i] = cs_gpio; + + if (gpio_is_valid(cs_gpio)) { + if (gpio_request(cs_gpio, "ssp-pl022")) + dev_err(&adev->dev, + "could not request %d gpio\n", + cs_gpio); + else if (gpio_direction_output(cs_gpio, 1)) + dev_err(&adev->dev, + "could set gpio %d as output\n", + cs_gpio); + } + } + } /* * Supports mode 0-3, loopback, and active low CS. Transfers are @@ -2158,6 +2218,7 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) err_no_ioremap: amba_release_regions(adev); err_no_ioregion: + err_no_gpio: spi_master_put(master); err_no_master: err_no_pdata: -- cgit v1.2.3-70-g09d2 From 41962f90c605983fb04c23bab9c060c9f49ee4c3 Mon Sep 17 00:00:00 2001 From: Roland Stigge Date: Wed, 22 Aug 2012 15:49:19 +0200 Subject: spi/dt: DT bindings documentation: "num-cs" property for SPI controllers Several SPI controller drivers have defined differently named properties for the number of chip selects. Now adding "num-cs" as a reference name for new bindings. Signed-off-by: Roland Stigge Reviewed-by: Linus Walleij Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/spi-bus.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index e782add2e45..d2c33d0f533 100644 --- a/Documentation/devicetree/bindings/spi/spi-bus.txt +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt @@ -21,6 +21,9 @@ assumption that board specific platform code will be used to manage chip selects. Individual drivers can define additional properties to support describing the chip select layout. +Optional property: +- num-cs : total number of chipselects + SPI slave nodes must be children of the SPI master node and can contain the following properties. - reg - (required) chip select address of device. -- cgit v1.2.3-70-g09d2 From 38ab18caa0ad9c844ba60f9618c5de6d6954da3e Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Wed, 5 Sep 2012 11:04:36 +0200 Subject: spi: spi-gpio: Add DT bindings This patch adds DT bindings to the spi-gpio driver and some documentation about how to use it. Signed-off-by: Daniel Mack Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/spi-gpio.txt | 29 +++++++ drivers/spi/spi-gpio.c | 99 +++++++++++++++++++++- 2 files changed, 125 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/spi/spi-gpio.txt (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/spi-gpio.txt b/Documentation/devicetree/bindings/spi/spi-gpio.txt new file mode 100644 index 00000000000..8a824be1575 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-gpio.txt @@ -0,0 +1,29 @@ +SPI-GPIO devicetree bindings + +Required properties: + + - compatible: should be set to "spi-gpio" + - #address-cells: should be set to <0x1> + - ranges + - gpio-sck: GPIO spec for the SCK line to use + - gpio-miso: GPIO spec for the MISO line to use + - gpio-mosi: GPIO spec for the MOSI line to use + - cs-gpios: GPIOs to use for chipselect lines + - num-chipselects: number of chipselect lines + +Example: + + spi { + compatible = "spi-gpio"; + #address-cells = <0x1>; + ranges; + + gpio-sck = <&gpio 95 0>; + gpio-miso = <&gpio 98 0>; + gpio-mosi = <&gpio 97 0>; + cs-gpios = <&gpio 125 0>; + num-chipselects = <1>; + + /* clients */ + }; + diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c index ff7263ce12c..aed16159584 100644 --- a/drivers/spi/spi-gpio.c +++ b/drivers/spi/spi-gpio.c @@ -22,6 +22,8 @@ #include #include #include +#include +#include #include #include @@ -232,13 +234,27 @@ static void spi_gpio_chipselect(struct spi_device *spi, int is_active) static int spi_gpio_setup(struct spi_device *spi) { - unsigned int cs = (unsigned int) spi->controller_data; + unsigned int cs; int status = 0; struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); + struct device_node *np = spi->master->dev.of_node; if (spi->bits_per_word > 32) return -EINVAL; + if (np) { + /* + * In DT environments, the CS GPIOs have already been + * initialized from the "cs-gpios" property of the node. + */ + cs = spi_gpio->cs_gpios[spi->chip_select]; + } else { + /* + * ... otherwise, take it from spi->controller_data + */ + cs = (unsigned int) spi->controller_data; + } + if (!spi->controller_state) { if (cs != SPI_GPIO_NO_CHIPSELECT) { status = gpio_request(cs, dev_name(&spi->dev)); @@ -250,6 +266,7 @@ static int spi_gpio_setup(struct spi_device *spi) } if (!status) { status = spi_bitbang_setup(spi); + /* in case it was initialized from static board data */ spi_gpio->cs_gpios[spi->chip_select] = cs; } @@ -326,6 +343,55 @@ done: return value; } +#ifdef CONFIG_OF +static struct of_device_id spi_gpio_dt_ids[] = { + { .compatible = "spi-gpio" }, + {} +}; +MODULE_DEVICE_TABLE(of, spi_gpio_dt_ids); + +static int spi_gpio_probe_dt(struct platform_device *pdev) +{ + int ret; + u32 tmp; + struct spi_gpio_platform_data *pdata; + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *of_id = + of_match_device(spi_gpio_dt_ids, &pdev->dev); + + if (!of_id) + return 0; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->sck = of_get_named_gpio(np, "gpio-sck", 0); + pdata->miso = of_get_named_gpio(np, "gpio-miso", 0); + pdata->mosi = of_get_named_gpio(np, "gpio-mosi", 0); + + ret = of_property_read_u32(np, "num-chipselects", &tmp); + if (ret < 0) { + dev_err(&pdev->dev, "num-chipselects property not found\n"); + goto error_free; + } + + pdata->num_chipselect = tmp; + pdev->dev.platform_data = pdata; + + return 1; + +error_free: + devm_kfree(&pdev->dev, pdata); + return ret; +} +#else +static inline int spi_probe_dt(struct platform_device *) +{ + return 0; +} +#endif + static int __devinit spi_gpio_probe(struct platform_device *pdev) { int status; @@ -333,6 +399,13 @@ static int __devinit spi_gpio_probe(struct platform_device *pdev) struct spi_gpio *spi_gpio; struct spi_gpio_platform_data *pdata; u16 master_flags = 0; + bool use_of = 0; + + status = spi_gpio_probe_dt(pdev); + if (status < 0) + return status; + if (status > 0) + use_of = 1; pdata = pdev->dev.platform_data; #ifdef GENERIC_BITBANG @@ -362,6 +435,23 @@ static int __devinit spi_gpio_probe(struct platform_device *pdev) master->num_chipselect = SPI_N_CHIPSEL; master->setup = spi_gpio_setup; master->cleanup = spi_gpio_cleanup; +#ifdef CONFIG_OF + master->dev.of_node = pdev->dev.of_node; + + if (use_of) { + int i; + struct device_node *np = pdev->dev.of_node; + + /* + * In DT environments, take the CS GPIO from the "cs-gpios" + * property of the node. + */ + + for (i = 0; i < SPI_N_CHIPSEL; i++) + spi_gpio->cs_gpios[i] = + of_get_named_gpio(np, "cs-gpios", i); + } +#endif spi_gpio->bitbang.master = spi_master_get(master); spi_gpio->bitbang.chipselect = spi_gpio_chipselect; @@ -422,8 +512,11 @@ static int __devexit spi_gpio_remove(struct platform_device *pdev) MODULE_ALIAS("platform:" DRIVER_NAME); static struct platform_driver spi_gpio_driver = { - .driver.name = DRIVER_NAME, - .driver.owner = THIS_MODULE, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(spi_gpio_dt_ids), + }, .probe = spi_gpio_probe, .remove = __devexit_p(spi_gpio_remove), }; -- cgit v1.2.3-70-g09d2 From e64d07a2dae569fc3c938adac777562a1d6f151e Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Wed, 22 Aug 2012 22:38:35 +0200 Subject: spi/mxs: Make the SPI block clock speed configurable via DT Add "clock-frequency" property, which allows configuring the SPI block's base speed. Signed-off-by: Marek Vasut Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/spi/mxs-spi.txt | 4 ++++ drivers/spi/spi-mxs.c | 21 +++++++++++++++------ 2 files changed, 19 insertions(+), 6 deletions(-) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/mxs-spi.txt b/Documentation/devicetree/bindings/spi/mxs-spi.txt index c36296f5ad2..e2e13957c2a 100644 --- a/Documentation/devicetree/bindings/spi/mxs-spi.txt +++ b/Documentation/devicetree/bindings/spi/mxs-spi.txt @@ -6,6 +6,10 @@ Required properties: - interrupts: Should contain SSP interrupts (error irq first, dma irq second) - fsl,ssp-dma-channel: APBX DMA channel for the SSP +Optional properties: +- clock-frequency : Input clock frequency to the SPI block in Hz. + Default is 160000000 Hz. + Example: ssp0: ssp@80010000 { diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c index 556e5ef907f..edf1360ab09 100644 --- a/drivers/spi/spi-mxs.c +++ b/drivers/spi/spi-mxs.c @@ -520,10 +520,17 @@ static int __devinit mxs_spi_probe(struct platform_device *pdev) struct pinctrl *pinctrl; struct clk *clk; void __iomem *base; - int devid, dma_channel; + int devid, dma_channel, clk_freq; int ret = 0, irq_err, irq_dma; dma_cap_mask_t mask; + /* + * Default clock speed for the SPI core. 160MHz seems to + * work reasonably well with most SPI flashes, so use this + * as a default. Override with "clock-frequency" DT prop. + */ + const int clk_freq_default = 160000000; + iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); irq_err = platform_get_irq(pdev, 0); irq_dma = platform_get_irq(pdev, 1); @@ -555,12 +562,18 @@ static int __devinit mxs_spi_probe(struct platform_device *pdev) "Failed to get DMA channel\n"); return -EINVAL; } + + ret = of_property_read_u32(np, "clock-frequency", + &clk_freq); + if (ret) + clk_freq = clk_freq_default; } else { dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0); if (!dmares) return -EINVAL; devid = pdev->id_entry->driver_data; dma_channel = dmares->start; + clk_freq = clk_freq_default; } master = spi_alloc_master(&pdev->dev, sizeof(*spi)); @@ -598,12 +611,8 @@ static int __devinit mxs_spi_probe(struct platform_device *pdev) goto out_master_free; } - /* - * Crank up the clock to 120MHz, this will be further divided onto a - * proper speed. - */ clk_prepare_enable(ssp->clk); - clk_set_rate(ssp->clk, 120 * 1000 * 1000); + clk_set_rate(ssp->clk, clk_freq); ssp->clk_rate = clk_get_rate(ssp->clk) / 1000; stmp_reset_block(ssp->base); -- cgit v1.2.3-70-g09d2 From 39a6ac11df6579df0361922f05c43f0fac8daa37 Mon Sep 17 00:00:00 2001 From: Roland Stigge Date: Tue, 18 Sep 2012 15:53:53 +0200 Subject: spi/pl022: Devicetree support w/o platform data Even with devicetree support, we needed platform data to provide some data, leading to mixed device tree and platform data. This patch makes it possible to provide all that information via device tree. Now, the data must be provided via platform data _or_ device tree completely. Only in case of DMA where a callback specification is necessary (dma_filter()), platform data is the only option. Signed-off-by: Roland Stigge Acked-by: Arnd Bergmann Acked-by: Linus Walleij Signed-off-by: Mark Brown --- .../devicetree/bindings/spi/spi_pl022.txt | 7 ++++ drivers/spi/spi-pl022.c | 39 +++++++++++++++++++--- 2 files changed, 41 insertions(+), 5 deletions(-) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/spi/spi_pl022.txt b/Documentation/devicetree/bindings/spi/spi_pl022.txt index 877f832c30a..f158fd31cfd 100644 --- a/Documentation/devicetree/bindings/spi/spi_pl022.txt +++ b/Documentation/devicetree/bindings/spi/spi_pl022.txt @@ -10,6 +10,13 @@ Optional properties: - cs-gpios : should specify GPIOs used for chipselects. The gpios will be referred to as reg = in the SPI child nodes. If unspecified, a single SPI device without a chip select can be used. +- pl022,autosuspend-delay : delay in ms following transfer completion before + the runtime power management system suspends the + device. A setting of 0 indicates no delay and the + device will be suspended immediately +- pl022,rt : indicates the controller should run the message pump with realtime + priority to minimise the transfer latency on the bus (boolean) + SPI slave nodes must be children of the SPI master node and can contain the following properties. diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index b6cfb7b3a59..3f2f36c79ab 100644 --- a/drivers/spi/spi-pl022.c +++ b/drivers/spi/spi-pl022.c @@ -2029,6 +2029,34 @@ static void pl022_cleanup(struct spi_device *spi) kfree(chip); } +static struct pl022_ssp_controller * +pl022_platform_data_dt_get(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct pl022_ssp_controller *pd; + u32 tmp; + + if (!np) { + dev_err(dev, "no dt node defined\n"); + return NULL; + } + + pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL); + if (!pd) { + dev_err(dev, "cannot allocate platform data memory\n"); + return NULL; + } + + pd->bus_id = -1; + of_property_read_u32(np, "num-cs", &tmp); + pd->num_chipselect = tmp; + of_property_read_u32(np, "pl022,autosuspend-delay", + &pd->autosuspend_delay); + pd->rt = of_property_read_bool(np, "pl022,rt"); + + return pd; +} + static int __devinit pl022_probe(struct amba_device *adev, const struct amba_id *id) { @@ -2041,18 +2069,19 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) dev_info(&adev->dev, "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); - if (platform_info == NULL) { - dev_err(&adev->dev, "probe - no platform data supplied\n"); + if (!platform_info && IS_ENABLED(CONFIG_OF)) + platform_info = pl022_platform_data_dt_get(dev); + + if (!platform_info) { + dev_err(dev, "probe: no platform data defined\n"); status = -ENODEV; goto err_no_pdata; } if (platform_info->num_chipselect) { num_cs = platform_info->num_chipselect; - } else if (IS_ENABLED(CONFIG_OF)) { - of_property_read_u32(np, "num-cs", &num_cs); } else { - dev_err(&adev->dev, "probe: no chip select defined\n"); + dev_err(dev, "probe: no chip select defined\n"); status = -ENODEV; goto err_no_pdata; } -- cgit v1.2.3-70-g09d2