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-rw-r--r--target/linux/brcm2708/patches-4.1/0019-Add-Chris-Boot-s-spi-driver.patch901
1 files changed, 901 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.1/0019-Add-Chris-Boot-s-spi-driver.patch b/target/linux/brcm2708/patches-4.1/0019-Add-Chris-Boot-s-spi-driver.patch
new file mode 100644
index 0000000..03d594c
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.1/0019-Add-Chris-Boot-s-spi-driver.patch
@@ -0,0 +1,901 @@
+From f5d52c99c98af7b3d50c6c9650422cb9fd8b495e Mon Sep 17 00:00:00 2001
+From: popcornmix <popcornmix@gmail.com>
+Date: Wed, 17 Jun 2015 15:41:33 +0100
+Subject: [PATCH 019/203] Add Chris Boot's spi driver.
+
+spi: bcm2708: add device tree support
+
+Add DT support to driver and add to .dtsi file.
+Setup pins and spidev in .dts file.
+SPI is disabled by default.
+
+Signed-off-by: Noralf Tronnes <notro@tronnes.org>
+
+BCM2708: don't register SPI controller when using DT
+
+The device for the SPI controller is in the Device Tree.
+Only register the device when not using DT.
+
+Signed-off-by: Noralf Tronnes <notro@tronnes.org>
+
+spi: bcm2835: make driver available on ARCH_BCM2708
+
+Make this driver available on ARCH_BCM2708
+
+Signed-off-by: Noralf Tronnes <notro@tronnes.org>
+
+bcm2708: Remove the prohibition on mixing SPIDEV and DT
+
+spi-bcm2708: Prepare for Common Clock Framework migration
+
+As part of migrating to use the Common Clock Framework, replace clk_enable()
+with clk_prepare_enable() and clk_disable() with clk_disable_unprepare().
+This does not affect behaviour under the current clock implementation.
+
+Also add a missing clk_disable_unprepare() in the probe error path.
+
+Signed-off-by: Noralf Tronnes <notro@tronnes.org>
+---
+ arch/arm/mach-bcm2708/Kconfig | 7 +
+ arch/arm/mach-bcm2708/bcm2708.c | 53 ++++
+ arch/arm/mach-bcm2709/bcm2709.c | 53 ++++
+ drivers/spi/Kconfig | 10 +-
+ drivers/spi/Makefile | 1 +
+ drivers/spi/spi-bcm2708.c | 635 ++++++++++++++++++++++++++++++++++++++++
+ 6 files changed, 758 insertions(+), 1 deletion(-)
+ create mode 100644 drivers/spi/spi-bcm2708.c
+
+--- a/arch/arm/mach-bcm2708/Kconfig
++++ b/arch/arm/mach-bcm2708/Kconfig
+@@ -35,4 +35,11 @@ config BCM2708_NOL2CACHE
+ help
+ Do not allow ARM to use GPU's L2 cache. Requires disable_l2cache in config.txt.
+
++config BCM2708_SPIDEV
++ bool "Bind spidev to SPI0 master"
++ depends on MACH_BCM2708
++ depends on SPI
++ default y
++ help
++ Binds spidev driver to the SPI0 master
+ endmenu
+--- a/arch/arm/mach-bcm2708/bcm2708.c
++++ b/arch/arm/mach-bcm2708/bcm2708.c
+@@ -34,6 +34,7 @@
+ #include <linux/io.h>
+ #include <linux/module.h>
+ #include <linux/of_platform.h>
++#include <linux/spi/spi.h>
+ #include <linux/gpio/machine.h>
+
+ #include <linux/version.h>
+@@ -505,6 +506,50 @@ static struct platform_device bcm2708_al
+ },
+ };
+
++static struct resource bcm2708_spi_resources[] = {
++ {
++ .start = SPI0_BASE,
++ .end = SPI0_BASE + SZ_256 - 1,
++ .flags = IORESOURCE_MEM,
++ }, {
++ .start = IRQ_SPI,
++ .end = IRQ_SPI,
++ .flags = IORESOURCE_IRQ,
++ }
++};
++
++
++static u64 bcm2708_spi_dmamask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON);
++static struct platform_device bcm2708_spi_device = {
++ .name = "bcm2708_spi",
++ .id = 0,
++ .num_resources = ARRAY_SIZE(bcm2708_spi_resources),
++ .resource = bcm2708_spi_resources,
++ .dev = {
++ .dma_mask = &bcm2708_spi_dmamask,
++ .coherent_dma_mask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON)},
++};
++
++#ifdef CONFIG_BCM2708_SPIDEV
++static struct spi_board_info bcm2708_spi_devices[] = {
++#ifdef CONFIG_SPI_SPIDEV
++ {
++ .modalias = "spidev",
++ .max_speed_hz = 500000,
++ .bus_num = 0,
++ .chip_select = 0,
++ .mode = SPI_MODE_0,
++ }, {
++ .modalias = "spidev",
++ .max_speed_hz = 500000,
++ .bus_num = 0,
++ .chip_select = 1,
++ .mode = SPI_MODE_0,
++ }
++#endif
++};
++#endif
++
+ static struct platform_device bcm2835_thermal_device = {
+ .name = "bcm2835_thermal",
+ };
+@@ -655,6 +700,8 @@ void __init bcm2708_init(void)
+ for (i = 0; i < ARRAY_SIZE(bcm2708_alsa_devices); i++)
+ bcm_register_device_dt(&bcm2708_alsa_devices[i]);
+
++ bcm_register_device_dt(&bcm2708_spi_device);
++
+ bcm_register_device_dt(&bcm2835_thermal_device);
+
+ if (!use_dt) {
+@@ -665,6 +712,12 @@ void __init bcm2708_init(void)
+ }
+ system_rev = boardrev;
+ system_serial_low = serial;
++
++#ifdef CONFIG_BCM2708_SPIDEV
++ if (!use_dt)
++ spi_register_board_info(bcm2708_spi_devices,
++ ARRAY_SIZE(bcm2708_spi_devices));
++#endif
+ }
+
+ static void timer_set_mode(enum clock_event_mode mode,
+--- a/arch/arm/mach-bcm2709/bcm2709.c
++++ b/arch/arm/mach-bcm2709/bcm2709.c
+@@ -34,6 +34,7 @@
+ #include <linux/io.h>
+ #include <linux/module.h>
+ #include <linux/of_platform.h>
++#include <linux/spi/spi.h>
+ #include <linux/gpio/machine.h>
+
+ #include <linux/version.h>
+@@ -525,6 +526,50 @@ static struct platform_device bcm2708_al
+ },
+ };
+
++static struct resource bcm2708_spi_resources[] = {
++ {
++ .start = SPI0_BASE,
++ .end = SPI0_BASE + SZ_256 - 1,
++ .flags = IORESOURCE_MEM,
++ }, {
++ .start = IRQ_SPI,
++ .end = IRQ_SPI,
++ .flags = IORESOURCE_IRQ,
++ }
++};
++
++
++static u64 bcm2708_spi_dmamask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON);
++static struct platform_device bcm2708_spi_device = {
++ .name = "bcm2708_spi",
++ .id = 0,
++ .num_resources = ARRAY_SIZE(bcm2708_spi_resources),
++ .resource = bcm2708_spi_resources,
++ .dev = {
++ .dma_mask = &bcm2708_spi_dmamask,
++ .coherent_dma_mask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON)},
++};
++
++#ifdef CONFIG_BCM2708_SPIDEV
++static struct spi_board_info bcm2708_spi_devices[] = {
++#ifdef CONFIG_SPI_SPIDEV
++ {
++ .modalias = "spidev",
++ .max_speed_hz = 500000,
++ .bus_num = 0,
++ .chip_select = 0,
++ .mode = SPI_MODE_0,
++ }, {
++ .modalias = "spidev",
++ .max_speed_hz = 500000,
++ .bus_num = 0,
++ .chip_select = 1,
++ .mode = SPI_MODE_0,
++ }
++#endif
++};
++#endif
++
+ static struct platform_device bcm2835_thermal_device = {
+ .name = "bcm2835_thermal",
+ };
+@@ -675,6 +720,8 @@ void __init bcm2709_init(void)
+ for (i = 0; i < ARRAY_SIZE(bcm2708_alsa_devices); i++)
+ bcm_register_device_dt(&bcm2708_alsa_devices[i]);
+
++ bcm_register_device_dt(&bcm2708_spi_device);
++
+ bcm_register_device_dt(&bcm2835_thermal_device);
+
+ if (!use_dt) {
+@@ -685,6 +732,12 @@ void __init bcm2709_init(void)
+ }
+ system_rev = boardrev;
+ system_serial_low = serial;
++
++#ifdef CONFIG_BCM2708_SPIDEV
++ if (!use_dt)
++ spi_register_board_info(bcm2708_spi_devices,
++ ARRAY_SIZE(bcm2708_spi_devices));
++#endif
+ }
+
+ #ifdef SYSTEM_TIMER
+--- a/drivers/spi/Kconfig
++++ b/drivers/spi/Kconfig
+@@ -77,7 +77,7 @@ config SPI_ATMEL
+
+ config SPI_BCM2835
+ tristate "BCM2835 SPI controller"
+- depends on ARCH_BCM2835 || COMPILE_TEST
++ depends on ARCH_BCM2835 || ARCH_BCM2708 || ARCH_BCM2709 || COMPILE_TEST
+ depends on GPIOLIB
+ help
+ This selects a driver for the Broadcom BCM2835 SPI master.
+@@ -87,6 +87,14 @@ config SPI_BCM2835
+ is for the regular SPI controller. Slave mode operation is not also
+ not supported.
+
++config SPI_BCM2708
++ tristate "BCM2708 SPI controller driver (SPI0)"
++ depends on MACH_BCM2708 || MACH_BCM2709
++ help
++ This selects a driver for the Broadcom BCM2708 SPI master (SPI0). This
++ driver is not compatible with the "Universal SPI Master" or the SPI slave
++ device.
++
+ config SPI_BFIN5XX
+ tristate "SPI controller driver for ADI Blackfin5xx"
+ depends on BLACKFIN && !BF60x
+--- a/drivers/spi/Makefile
++++ b/drivers/spi/Makefile
+@@ -20,6 +20,7 @@ obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63x
+ obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o
+ obj-$(CONFIG_SPI_BFIN5XX) += spi-bfin5xx.o
+ obj-$(CONFIG_SPI_ADI_V3) += spi-adi-v3.o
++obj-$(CONFIG_SPI_BCM2708) += spi-bcm2708.o
+ obj-$(CONFIG_SPI_BFIN_SPORT) += spi-bfin-sport.o
+ obj-$(CONFIG_SPI_BITBANG) += spi-bitbang.o
+ obj-$(CONFIG_SPI_BUTTERFLY) += spi-butterfly.o
+--- /dev/null
++++ b/drivers/spi/spi-bcm2708.c
+@@ -0,0 +1,635 @@
++/*
++ * Driver for Broadcom BCM2708 SPI Controllers
++ *
++ * Copyright (C) 2012 Chris Boot
++ *
++ * This driver is inspired by:
++ * spi-ath79.c, Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
++ * spi-atmel.c, Copyright (C) 2006 Atmel Corporation
++ *
++ * 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 <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/spinlock.h>
++#include <linux/clk.h>
++#include <linux/err.h>
++#include <linux/platform_device.h>
++#include <linux/io.h>
++#include <linux/spi/spi.h>
++#include <linux/interrupt.h>
++#include <linux/delay.h>
++#include <linux/log2.h>
++#include <linux/sched.h>
++#include <linux/wait.h>
++
++/* SPI register offsets */
++#define SPI_CS 0x00
++#define SPI_FIFO 0x04
++#define SPI_CLK 0x08
++#define SPI_DLEN 0x0c
++#define SPI_LTOH 0x10
++#define SPI_DC 0x14
++
++/* Bitfields in CS */
++#define SPI_CS_LEN_LONG 0x02000000
++#define SPI_CS_DMA_LEN 0x01000000
++#define SPI_CS_CSPOL2 0x00800000
++#define SPI_CS_CSPOL1 0x00400000
++#define SPI_CS_CSPOL0 0x00200000
++#define SPI_CS_RXF 0x00100000
++#define SPI_CS_RXR 0x00080000
++#define SPI_CS_TXD 0x00040000
++#define SPI_CS_RXD 0x00020000
++#define SPI_CS_DONE 0x00010000
++#define SPI_CS_LEN 0x00002000
++#define SPI_CS_REN 0x00001000
++#define SPI_CS_ADCS 0x00000800
++#define SPI_CS_INTR 0x00000400
++#define SPI_CS_INTD 0x00000200
++#define SPI_CS_DMAEN 0x00000100
++#define SPI_CS_TA 0x00000080
++#define SPI_CS_CSPOL 0x00000040
++#define SPI_CS_CLEAR_RX 0x00000020
++#define SPI_CS_CLEAR_TX 0x00000010
++#define SPI_CS_CPOL 0x00000008
++#define SPI_CS_CPHA 0x00000004
++#define SPI_CS_CS_10 0x00000002
++#define SPI_CS_CS_01 0x00000001
++
++#define SPI_TIMEOUT_MS 150
++
++#define DRV_NAME "bcm2708_spi"
++
++struct bcm2708_spi {
++ spinlock_t lock;
++ void __iomem *base;
++ int irq;
++ struct clk *clk;
++ bool stopping;
++
++ struct list_head queue;
++ struct workqueue_struct *workq;
++ struct work_struct work;
++ struct completion done;
++
++ const u8 *tx_buf;
++ u8 *rx_buf;
++ int len;
++};
++
++struct bcm2708_spi_state {
++ u32 cs;
++ u16 cdiv;
++};
++
++/*
++ * This function sets the ALT mode on the SPI pins so that we can use them with
++ * the SPI hardware.
++ *
++ * FIXME: This is a hack. Use pinmux / pinctrl.
++ */
++static void bcm2708_init_pinmode(void)
++{
++#define INP_GPIO(g) *(gpio+((g)/10)) &= ~(7<<(((g)%10)*3))
++#define SET_GPIO_ALT(g,a) *(gpio+(((g)/10))) |= (((a)<=3?(a)+4:(a)==4?3:2)<<(((g)%10)*3))
++
++ int pin;
++ u32 *gpio = ioremap(GPIO_BASE, SZ_16K);
++
++ /* SPI is on GPIO 7..11 */
++ for (pin = 7; pin <= 11; pin++) {
++ INP_GPIO(pin); /* set mode to GPIO input first */
++ SET_GPIO_ALT(pin, 0); /* set mode to ALT 0 */
++ }
++
++ iounmap(gpio);
++
++#undef INP_GPIO
++#undef SET_GPIO_ALT
++}
++
++static inline u32 bcm2708_rd(struct bcm2708_spi *bs, unsigned reg)
++{
++ return readl(bs->base + reg);
++}
++
++static inline void bcm2708_wr(struct bcm2708_spi *bs, unsigned reg, u32 val)
++{
++ writel(val, bs->base + reg);
++}
++
++static inline void bcm2708_rd_fifo(struct bcm2708_spi *bs, int len)
++{
++ u8 byte;
++
++ while (len--) {
++ byte = bcm2708_rd(bs, SPI_FIFO);
++ if (bs->rx_buf)
++ *bs->rx_buf++ = byte;
++ }
++}
++
++static inline void bcm2708_wr_fifo(struct bcm2708_spi *bs, int len)
++{
++ u8 byte;
++ u16 val;
++
++ if (len > bs->len)
++ len = bs->len;
++
++ if (unlikely(bcm2708_rd(bs, SPI_CS) & SPI_CS_LEN)) {
++ /* LoSSI mode */
++ if (unlikely(len % 2)) {
++ printk(KERN_ERR"bcm2708_wr_fifo: length must be even, skipping.\n");
++ bs->len = 0;
++ return;
++ }
++ while (len) {
++ if (bs->tx_buf) {
++ val = *(const u16 *)bs->tx_buf;
++ bs->tx_buf += 2;
++ } else
++ val = 0;
++ bcm2708_wr(bs, SPI_FIFO, val);
++ bs->len -= 2;
++ len -= 2;
++ }
++ return;
++ }
++
++ while (len--) {
++ byte = bs->tx_buf ? *bs->tx_buf++ : 0;
++ bcm2708_wr(bs, SPI_FIFO, byte);
++ bs->len--;
++ }
++}
++
++static irqreturn_t bcm2708_spi_interrupt(int irq, void *dev_id)
++{
++ struct spi_master *master = dev_id;
++ struct bcm2708_spi *bs = spi_master_get_devdata(master);
++ u32 cs;
++
++ spin_lock(&bs->lock);
++
++ cs = bcm2708_rd(bs, SPI_CS);
++
++ if (cs & SPI_CS_DONE) {
++ if (bs->len) { /* first interrupt in a transfer */
++ /* fill the TX fifo with up to 16 bytes */
++ bcm2708_wr_fifo(bs, 16);
++ } else { /* transfer complete */
++ /* disable interrupts */
++ cs &= ~(SPI_CS_INTR | SPI_CS_INTD);
++ bcm2708_wr(bs, SPI_CS, cs);
++
++ /* drain RX FIFO */
++ while (cs & SPI_CS_RXD) {
++ bcm2708_rd_fifo(bs, 1);
++ cs = bcm2708_rd(bs, SPI_CS);
++ }
++
++ /* wake up our bh */
++ complete(&bs->done);
++ }
++ } else if (cs & SPI_CS_RXR) {
++ /* read 12 bytes of data */
++ bcm2708_rd_fifo(bs, 12);
++
++ /* write up to 12 bytes */
++ bcm2708_wr_fifo(bs, 12);
++ }
++
++ spin_unlock(&bs->lock);
++
++ return IRQ_HANDLED;
++}
++
++static int bcm2708_setup_state(struct spi_master *master,
++ struct device *dev, struct bcm2708_spi_state *state,
++ u32 hz, u8 csel, u8 mode, u8 bpw)
++{
++ struct bcm2708_spi *bs = spi_master_get_devdata(master);
++ int cdiv;
++ unsigned long bus_hz;
++ u32 cs = 0;
++
++ bus_hz = clk_get_rate(bs->clk);
++
++ if (hz >= bus_hz) {
++ cdiv = 2; /* bus_hz / 2 is as fast as we can go */
++ } else if (hz) {
++ cdiv = DIV_ROUND_UP(bus_hz, hz);
++
++ /* CDIV must be a power of 2, so round up */
++ cdiv = roundup_pow_of_two(cdiv);
++
++ if (cdiv > 65536) {
++ dev_dbg(dev,
++ "setup: %d Hz too slow, cdiv %u; min %ld Hz\n",
++ hz, cdiv, bus_hz / 65536);
++ return -EINVAL;
++ } else if (cdiv == 65536) {
++ cdiv = 0;
++ } else if (cdiv == 1) {
++ cdiv = 2; /* 1 gets rounded down to 0; == 65536 */
++ }
++ } else {
++ cdiv = 0;
++ }
++
++ switch (bpw) {
++ case 8:
++ break;
++ case 9:
++ /* Reading in LoSSI mode is a special case. See 'BCM2835 ARM Peripherals' datasheet */
++ cs |= SPI_CS_LEN;
++ break;
++ default:
++ dev_dbg(dev, "setup: invalid bits_per_word %u (must be 8 or 9)\n",
++ bpw);
++ return -EINVAL;
++ }
++
++ if (mode & SPI_CPOL)
++ cs |= SPI_CS_CPOL;
++ if (mode & SPI_CPHA)
++ cs |= SPI_CS_CPHA;
++
++ if (!(mode & SPI_NO_CS)) {
++ if (mode & SPI_CS_HIGH) {
++ cs |= SPI_CS_CSPOL;
++ cs |= SPI_CS_CSPOL0 << csel;
++ }
++
++ cs |= csel;
++ } else {
++ cs |= SPI_CS_CS_10 | SPI_CS_CS_01;
++ }
++
++ if (state) {
++ state->cs = cs;
++ state->cdiv = cdiv;
++ dev_dbg(dev, "setup: want %d Hz; "
++ "bus_hz=%lu / cdiv=%u == %lu Hz; "
++ "mode %u: cs 0x%08X\n",
++ hz, bus_hz, cdiv, bus_hz/cdiv, mode, cs);
++ }
++
++ return 0;
++}
++
++static int bcm2708_process_transfer(struct bcm2708_spi *bs,
++ struct spi_message *msg, struct spi_transfer *xfer)
++{
++ struct spi_device *spi = msg->spi;
++ struct bcm2708_spi_state state, *stp;
++ int ret;
++ u32 cs;
++
++ if (bs->stopping)
++ return -ESHUTDOWN;
++
++ if (xfer->bits_per_word || xfer->speed_hz) {
++ ret = bcm2708_setup_state(spi->master, &spi->dev, &state,
++ xfer->speed_hz ? xfer->speed_hz : spi->max_speed_hz,
++ spi->chip_select, spi->mode,
++ xfer->bits_per_word ? xfer->bits_per_word :
++ spi->bits_per_word);
++ if (ret)
++ return ret;
++
++ stp = &state;
++ } else {
++ stp = spi->controller_state;
++ }
++
++ reinit_completion(&bs->done);
++ bs->tx_buf = xfer->tx_buf;
++ bs->rx_buf = xfer->rx_buf;
++ bs->len = xfer->len;
++
++ cs = stp->cs | SPI_CS_INTR | SPI_CS_INTD | SPI_CS_TA;
++
++ bcm2708_wr(bs, SPI_CLK, stp->cdiv);
++ bcm2708_wr(bs, SPI_CS, cs);
++
++ ret = wait_for_completion_timeout(&bs->done,
++ msecs_to_jiffies(SPI_TIMEOUT_MS));
++ if (ret == 0) {
++ dev_err(&spi->dev, "transfer timed out\n");
++ return -ETIMEDOUT;
++ }
++
++ if (xfer->delay_usecs)
++ udelay(xfer->delay_usecs);
++
++ if (list_is_last(&xfer->transfer_list, &msg->transfers) ||
++ xfer->cs_change) {
++ /* clear TA and interrupt flags */
++ bcm2708_wr(bs, SPI_CS, stp->cs);
++ }
++
++ msg->actual_length += (xfer->len - bs->len);
++
++ return 0;
++}
++
++static void bcm2708_work(struct work_struct *work)
++{
++ struct bcm2708_spi *bs = container_of(work, struct bcm2708_spi, work);
++ unsigned long flags;
++ struct spi_message *msg;
++ struct spi_transfer *xfer;
++ int status = 0;
++
++ spin_lock_irqsave(&bs->lock, flags);
++ while (!list_empty(&bs->queue)) {
++ msg = list_first_entry(&bs->queue, struct spi_message, queue);
++ list_del_init(&msg->queue);
++ spin_unlock_irqrestore(&bs->lock, flags);
++
++ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
++ status = bcm2708_process_transfer(bs, msg, xfer);
++ if (status)
++ break;
++ }
++
++ msg->status = status;
++ msg->complete(msg->context);
++
++ spin_lock_irqsave(&bs->lock, flags);
++ }
++ spin_unlock_irqrestore(&bs->lock, flags);
++}
++
++static int bcm2708_spi_setup(struct spi_device *spi)
++{
++ struct bcm2708_spi *bs = spi_master_get_devdata(spi->master);
++ struct bcm2708_spi_state *state;
++ int ret;
++
++ if (bs->stopping)
++ return -ESHUTDOWN;
++
++ if (!(spi->mode & SPI_NO_CS) &&
++ (spi->chip_select > spi->master->num_chipselect)) {
++ dev_dbg(&spi->dev,
++ "setup: invalid chipselect %u (%u defined)\n",
++ spi->chip_select, spi->master->num_chipselect);
++ return -EINVAL;
++ }
++
++ state = spi->controller_state;
++ if (!state) {
++ state = kzalloc(sizeof(*state), GFP_KERNEL);
++ if (!state)
++ return -ENOMEM;
++
++ spi->controller_state = state;
++ }
++
++ ret = bcm2708_setup_state(spi->master, &spi->dev, state,
++ spi->max_speed_hz, spi->chip_select, spi->mode,
++ spi->bits_per_word);
++ if (ret < 0) {
++ kfree(state);
++ spi->controller_state = NULL;
++ return ret;
++ }
++
++ dev_dbg(&spi->dev,
++ "setup: cd %d: %d Hz, bpw %u, mode 0x%x -> CS=%08x CDIV=%04x\n",
++ spi->chip_select, spi->max_speed_hz, spi->bits_per_word,
++ spi->mode, state->cs, state->cdiv);
++
++ return 0;
++}
++
++static int bcm2708_spi_transfer(struct spi_device *spi, struct spi_message *msg)
++{
++ struct bcm2708_spi *bs = spi_master_get_devdata(spi->master);
++ struct spi_transfer *xfer;
++ int ret;
++ unsigned long flags;
++
++ if (unlikely(list_empty(&msg->transfers)))
++ return -EINVAL;
++
++ if (bs->stopping)
++ return -ESHUTDOWN;
++
++ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
++ if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) {
++ dev_dbg(&spi->dev, "missing rx or tx buf\n");
++ return -EINVAL;
++ }
++
++ if (!xfer->bits_per_word || xfer->speed_hz)
++ continue;
++
++ ret = bcm2708_setup_state(spi->master, &spi->dev, NULL,
++ xfer->speed_hz ? xfer->speed_hz : spi->max_speed_hz,
++ spi->chip_select, spi->mode,
++ xfer->bits_per_word ? xfer->bits_per_word :
++ spi->bits_per_word);
++ if (ret)
++ return ret;
++ }
++
++ msg->status = -EINPROGRESS;
++ msg->actual_length = 0;
++
++ spin_lock_irqsave(&bs->lock, flags);
++ list_add_tail(&msg->queue, &bs->queue);
++ queue_work(bs->workq, &bs->work);
++ spin_unlock_irqrestore(&bs->lock, flags);
++
++ return 0;
++}
++
++static void bcm2708_spi_cleanup(struct spi_device *spi)
++{
++ if (spi->controller_state) {
++ kfree(spi->controller_state);
++ spi->controller_state = NULL;
++ }
++}
++
++static int bcm2708_spi_probe(struct platform_device *pdev)
++{
++ struct resource *regs;
++ int irq, err = -ENOMEM;
++ struct clk *clk;
++ struct spi_master *master;
++ struct bcm2708_spi *bs;
++
++ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ if (!regs) {
++ dev_err(&pdev->dev, "could not get IO memory\n");
++ return -ENXIO;
++ }
++
++ irq = platform_get_irq(pdev, 0);
++ if (irq < 0) {
++ dev_err(&pdev->dev, "could not get IRQ\n");
++ return irq;
++ }
++
++ clk = clk_get(&pdev->dev, NULL);
++ if (IS_ERR(clk)) {
++ dev_err(&pdev->dev, "could not find clk: %ld\n", PTR_ERR(clk));
++ return PTR_ERR(clk);
++ }
++
++ bcm2708_init_pinmode();
++
++ master = spi_alloc_master(&pdev->dev, sizeof(*bs));
++ if (!master) {
++ dev_err(&pdev->dev, "spi_alloc_master() failed\n");
++ goto out_clk_put;
++ }
++
++ /* the spi->mode bits understood by this driver: */
++ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
++
++ master->bus_num = pdev->id;
++ master->num_chipselect = 3;
++ master->setup = bcm2708_spi_setup;
++ master->transfer = bcm2708_spi_transfer;
++ master->cleanup = bcm2708_spi_cleanup;
++ master->dev.of_node = pdev->dev.of_node;
++ platform_set_drvdata(pdev, master);
++
++ bs = spi_master_get_devdata(master);
++
++ spin_lock_init(&bs->lock);
++ INIT_LIST_HEAD(&bs->queue);
++ init_completion(&bs->done);
++ INIT_WORK(&bs->work, bcm2708_work);
++
++ bs->base = ioremap(regs->start, resource_size(regs));
++ if (!bs->base) {
++ dev_err(&pdev->dev, "could not remap memory\n");
++ goto out_master_put;
++ }
++
++ bs->workq = create_singlethread_workqueue(dev_name(&pdev->dev));
++ if (!bs->workq) {
++ dev_err(&pdev->dev, "could not create workqueue\n");
++ goto out_iounmap;
++ }
++
++ bs->irq = irq;
++ bs->clk = clk;
++ bs->stopping = false;
++
++ err = request_irq(irq, bcm2708_spi_interrupt, 0, dev_name(&pdev->dev),
++ master);
++ if (err) {
++ dev_err(&pdev->dev, "could not request IRQ: %d\n", err);
++ goto out_workqueue;
++ }
++
++ /* initialise the hardware */
++ clk_prepare_enable(clk);
++ bcm2708_wr(bs, SPI_CS, SPI_CS_REN | SPI_CS_CLEAR_RX | SPI_CS_CLEAR_TX);
++
++ err = spi_register_master(master);
++ if (err) {
++ dev_err(&pdev->dev, "could not register SPI master: %d\n", err);
++ goto out_free_irq;
++ }
++
++ dev_info(&pdev->dev, "SPI Controller at 0x%08lx (irq %d)\n",
++ (unsigned long)regs->start, irq);
++
++ return 0;
++
++out_free_irq:
++ free_irq(bs->irq, master);
++ clk_disable_unprepare(bs->clk);
++out_workqueue:
++ destroy_workqueue(bs->workq);
++out_iounmap:
++ iounmap(bs->base);
++out_master_put:
++ spi_master_put(master);
++out_clk_put:
++ clk_put(clk);
++ return err;
++}
++
++static int bcm2708_spi_remove(struct platform_device *pdev)
++{
++ struct spi_master *master = platform_get_drvdata(pdev);
++ struct bcm2708_spi *bs = spi_master_get_devdata(master);
++
++ /* reset the hardware and block queue progress */
++ spin_lock_irq(&bs->lock);
++ bs->stopping = true;
++ bcm2708_wr(bs, SPI_CS, SPI_CS_CLEAR_RX | SPI_CS_CLEAR_TX);
++ spin_unlock_irq(&bs->lock);
++
++ flush_work(&bs->work);
++
++ clk_disable_unprepare(bs->clk);
++ clk_put(bs->clk);
++ free_irq(bs->irq, master);
++ iounmap(bs->base);
++
++ spi_unregister_master(master);
++
++ return 0;
++}
++
++static const struct of_device_id bcm2708_spi_match[] = {
++ { .compatible = "brcm,bcm2708-spi", },
++ {}
++};
++MODULE_DEVICE_TABLE(of, bcm2708_spi_match);
++
++static struct platform_driver bcm2708_spi_driver = {
++ .driver = {
++ .name = DRV_NAME,
++ .owner = THIS_MODULE,
++ .of_match_table = bcm2708_spi_match,
++ },
++ .probe = bcm2708_spi_probe,
++ .remove = bcm2708_spi_remove,
++};
++
++
++static int __init bcm2708_spi_init(void)
++{
++ return platform_driver_probe(&bcm2708_spi_driver, bcm2708_spi_probe);
++}
++module_init(bcm2708_spi_init);
++
++static void __exit bcm2708_spi_exit(void)
++{
++ platform_driver_unregister(&bcm2708_spi_driver);
++}
++module_exit(bcm2708_spi_exit);
++
++
++//module_platform_driver(bcm2708_spi_driver);
++
++MODULE_DESCRIPTION("SPI controller driver for Broadcom BCM2708");
++MODULE_AUTHOR("Chris Boot <bootc@bootc.net>");
++MODULE_LICENSE("GPL v2");
++MODULE_ALIAS("platform:" DRV_NAME);
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-15 14:31:58 +0000