[PATCH 2/3] spi: mediatek: Add spi bus for Mediatek MT8173
leilk.liu at mediatek.com
leilk.liu at mediatek.com
Fri May 8 01:55:42 PDT 2015
From: Leilk Liu <leilk.liu at mediatek.com>
This patch adds basic spi bus for MT8173.
Signed-off-by: Leilk Liu <leilk.liu at mediatek.com>
---
drivers/spi/Kconfig | 10 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-mt65xx.c | 622 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 633 insertions(+)
create mode 100644 drivers/spi/spi-mt65xx.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 198f96b..01239e0 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -324,6 +324,16 @@ config SPI_MESON_SPIFC
This enables master mode support for the SPIFC (SPI flash
controller) available in Amlogic Meson SoCs.
+config SPI_MT65XX
+ tristate "MediaTek SPI controller"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ select SPI_BITBANG
+ help
+ This selects the MediaTek(R) SPI bus driver.
+ If you want to use MediaTek(R) SPI interface,
+ say Y or M here.If you are not sure, say N.
+ SPI drivers for Mediatek mt65XX series ARM SoCs.
+
config SPI_OC_TINY
tristate "OpenCores tiny SPI"
depends on GPIOLIB
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d8cbf65..ab332ef 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o
obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o
obj-$(CONFIG_SPI_MPC52xx_PSC) += spi-mpc52xx-psc.o
obj-$(CONFIG_SPI_MPC52xx) += spi-mpc52xx.o
+obj-$(CONFIG_SPI_MT65XX) += spi-mt65xx.o
obj-$(CONFIG_SPI_MXS) += spi-mxs.o
obj-$(CONFIG_SPI_NUC900) += spi-nuc900.o
obj-$(CONFIG_SPI_OC_TINY) += spi-oc-tiny.o
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
new file mode 100644
index 0000000..92c119d
--- /dev/null
+++ b/drivers/spi/spi-mt65xx.c
@@ -0,0 +1,622 @@
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: Leilk Liu <leilk.liu at mediatek.com>
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/spi/spi.h>
+#include <linux/workqueue.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/gpio.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+
+#define SPI_CFG0_REG 0x0000
+#define SPI_CFG1_REG 0x0004
+#define SPI_TX_SRC_REG 0x0008
+#define SPI_RX_DST_REG 0x000c
+#define SPI_CMD_REG 0x0018
+#define SPI_STATUS0_REG 0x001c
+#define SPI_PAD_SEL_REG 0x0024
+
+#define SPI_CFG0_SCK_HIGH_OFFSET 0
+#define SPI_CFG0_SCK_LOW_OFFSET 8
+#define SPI_CFG0_CS_HOLD_OFFSET 16
+#define SPI_CFG0_CS_SETUP_OFFSET 24
+
+#define SPI_CFG0_SCK_HIGH_MASK 0xff
+#define SPI_CFG0_SCK_LOW_MASK 0xff00
+#define SPI_CFG0_CS_HOLD_MASK 0xff0000
+#define SPI_CFG0_CS_SETUP_MASK 0xff000000
+
+#define SPI_CFG1_CS_IDLE_OFFSET 0
+#define SPI_CFG1_PACKET_LOOP_OFFSET 8
+#define SPI_CFG1_PACKET_LENGTH_OFFSET 16
+#define SPI_CFG1_GET_TICK_DLY_OFFSET 30
+
+#define SPI_CFG1_CS_IDLE_MASK 0xff
+#define SPI_CFG1_PACKET_LOOP_MASK 0xff00
+#define SPI_CFG1_PACKET_LENGTH_MASK 0x3ff0000
+#define SPI_CFG1_GET_TICK_DLY_MASK 0xc0000000
+
+#define SPI_CMD_ACT_OFFSET 0
+#define SPI_CMD_RESUME_OFFSET 1
+#define SPI_CMD_RST_OFFSET 2
+#define SPI_CMD_PAUSE_EN_OFFSET 4
+#define SPI_CMD_DEASSERT_OFFSET 5
+#define SPI_CMD_CPHA_OFFSET 8
+#define SPI_CMD_CPOL_OFFSET 9
+#define SPI_CMD_RX_DMA_OFFSET 10
+#define SPI_CMD_TX_DMA_OFFSET 11
+#define SPI_CMD_TXMSBF_OFFSET 12
+#define SPI_CMD_RXMSBF_OFFSET 13
+#define SPI_CMD_RX_ENDIAN_OFFSET 14
+#define SPI_CMD_TX_ENDIAN_OFFSET 15
+#define SPI_CMD_FINISH_IE_OFFSET 16
+#define SPI_CMD_PAUSE_IE_OFFSET 17
+
+#define SPI_CMD_RESUME_MASK 0x2
+#define SPI_CMD_RST_MASK 0x4
+#define SPI_CMD_PAUSE_EN_MASK 0x10
+#define SPI_CMD_DEASSERT_MASK 0x20
+#define SPI_CMD_CPHA_MASK 0x100
+#define SPI_CMD_CPOL_MASK 0x200
+#define SPI_CMD_RX_DMA_MASK 0x400
+#define SPI_CMD_TX_DMA_MASK 0x800
+#define SPI_CMD_TXMSBF_MASK 0x1000
+#define SPI_CMD_RXMSBF_MASK 0x2000
+#define SPI_CMD_RX_ENDIAN_MASK 0x4000
+#define SPI_CMD_TX_ENDIAN_MASK 0x8000
+#define SPI_CMD_FINISH_IE_MASK 0x10000
+
+#define COMPAT_MT6589 (0x1 << 0)
+#define COMPAT_MT8173 (0x1 << 1)
+
+#define MT8173_MAX_PAD_SEL 3
+
+#define IDLE 0
+#define INPROGRESS 1
+#define PAUSED 2
+
+#define PACKET_SIZE 1024
+
+struct mtk_chip_config {
+ u32 setuptime;
+ u32 holdtime;
+ u32 high_time;
+ u32 low_time;
+ u32 cs_idletime;
+ u32 tx_mlsb;
+ u32 rx_mlsb;
+ u32 tx_endian;
+ u32 rx_endian;
+ u32 pause;
+ u32 finish_intr;
+ u32 deassert;
+ u32 tckdly;
+};
+
+struct mtk_spi_ddata {
+ struct spi_bitbang bitbang;
+ void __iomem *base;
+ u32 irq;
+ u32 state;
+ u32 platform_compat;
+ u32 pad_sel;
+ struct clk *clk;
+
+ const u8 *tx_buf;
+ u8 *rx_buf;
+ u32 tx_len, rx_len;
+ struct completion done;
+};
+
+/*
+ * A piece of default chip info unless the platform
+ * supplies it.
+ */
+static const struct mtk_chip_config mtk_default_chip_info = {
+ .setuptime = 10,
+ .holdtime = 12,
+ .high_time = 6,
+ .low_time = 6,
+ .cs_idletime = 12,
+ .rx_mlsb = 1,
+ .tx_mlsb = 1,
+ .tx_endian = 0,
+ .rx_endian = 0,
+ .pause = 0,
+ .finish_intr = 1,
+ .deassert = 0,
+ .tckdly = 0,
+};
+
+static const struct of_device_id mtk_spi_of_match[] = {
+ { .compatible = "mediatek,mt6589-spi", .data = (void *)COMPAT_MT6589},
+ { .compatible = "mediatek,mt8173-spi", .data = (void *)COMPAT_MT8173},
+ {}
+};
+MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
+
+static void mtk_spi_reset(struct mtk_spi_ddata *mdata)
+{
+ u32 reg_val;
+
+ /*set the software reset bit in SPI_CMD_REG.*/
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_RST_MASK;
+ reg_val |= 1 << SPI_CMD_RST_OFFSET;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_RST_MASK;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static void mtk_set_pause_bit(struct mtk_spi_ddata *mdata)
+{
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val |= 1 << SPI_CMD_PAUSE_EN_OFFSET;
+ reg_val |= 1 << SPI_CMD_PAUSE_IE_OFFSET;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static void mtk_clear_pause_bit(struct mtk_spi_ddata *mdata)
+{
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_PAUSE_EN_MASK;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static int mtk_spi_config(struct mtk_spi_ddata *mdata,
+ struct mtk_chip_config *chip_config)
+{
+ u32 reg_val;
+
+ /* set the timing */
+ reg_val = readl(mdata->base + SPI_CFG0_REG);
+ reg_val &= ~(SPI_CFG0_SCK_HIGH_MASK | SPI_CFG0_SCK_LOW_MASK);
+ reg_val &= ~(SPI_CFG0_CS_HOLD_MASK | SPI_CFG0_CS_SETUP_MASK);
+ reg_val |= ((chip_config->high_time - 1) << SPI_CFG0_SCK_HIGH_OFFSET);
+ reg_val |= ((chip_config->low_time - 1) << SPI_CFG0_SCK_LOW_OFFSET);
+ reg_val |= ((chip_config->holdtime - 1) << SPI_CFG0_CS_HOLD_OFFSET);
+ reg_val |= ((chip_config->setuptime - 1) << SPI_CFG0_CS_SETUP_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG0_REG);
+
+ reg_val = readl(mdata->base + SPI_CFG1_REG);
+ reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
+ reg_val |= ((chip_config->cs_idletime - 1) << SPI_CFG1_CS_IDLE_OFFSET);
+ reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK;
+ reg_val |= ((chip_config->tckdly) << SPI_CFG1_GET_TICK_DLY_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG1_REG);
+
+ /* set the mlsbx and mlsbtx */
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~(SPI_CMD_TX_ENDIAN_MASK | SPI_CMD_RX_ENDIAN_MASK);
+ reg_val &= ~(SPI_CMD_TXMSBF_MASK | SPI_CMD_RXMSBF_MASK);
+ reg_val |= (chip_config->tx_mlsb << SPI_CMD_TXMSBF_OFFSET);
+ reg_val |= (chip_config->rx_mlsb << SPI_CMD_RXMSBF_OFFSET);
+ reg_val |= (chip_config->tx_endian << SPI_CMD_TX_ENDIAN_OFFSET);
+ reg_val |= (chip_config->rx_endian << SPI_CMD_RX_ENDIAN_OFFSET);
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ /* set finish and pause interrupt always enable */
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_FINISH_IE_MASK;
+ reg_val |= (chip_config->finish_intr << SPI_CMD_FINISH_IE_OFFSET);
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val |= 1 << SPI_CMD_TX_DMA_OFFSET;
+ reg_val |= 1 << SPI_CMD_RX_DMA_OFFSET;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ /* set deassert mode */
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_DEASSERT_MASK;
+ reg_val |= (chip_config->deassert << SPI_CMD_DEASSERT_OFFSET);
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ /* pad select */
+ if (mdata->platform_compat & COMPAT_MT8173)
+ writel(mdata->pad_sel, mdata->base + SPI_PAD_SEL_REG);
+
+ return 0;
+}
+
+static int mtk_spi_setup_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ u32 reg_val;
+ struct spi_master *master = spi->master;
+ struct mtk_spi_ddata *mdata = spi_master_get_devdata(master);
+ struct spi_message *m = master->cur_msg;
+ struct mtk_chip_config *chip_config;
+
+ u8 cpha = spi->mode & SPI_CPHA ? 1 : 0;
+ u8 cpol = spi->mode & SPI_CPOL ? 1 : 0;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~(SPI_CMD_CPHA_MASK | SPI_CMD_CPOL_MASK);
+ reg_val |= (cpha << SPI_CMD_CPHA_OFFSET);
+ reg_val |= (cpol << SPI_CMD_CPOL_OFFSET);
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ if (t->cs_change) {
+ if (!(list_is_last(&t->transfer_list, &m->transfers)))
+ mdata->state = IDLE;
+ } else {
+ mdata->state = IDLE;
+ mtk_spi_reset(mdata);
+ }
+
+ chip_config = (struct mtk_chip_config *)spi->controller_data;
+ if (!chip_config) {
+ chip_config = (void *)&mtk_default_chip_info;
+ spi->controller_data = chip_config;
+ mdata->state = IDLE;
+ }
+
+ mtk_spi_config(mdata, chip_config);
+
+ return 0;
+}
+
+static void mtk_spi_chipselect(struct spi_device *spi, int is_on)
+{
+ struct mtk_spi_ddata *mdata = spi_master_get_devdata(spi->master);
+
+ switch (is_on) {
+ case BITBANG_CS_ACTIVE:
+ mtk_set_pause_bit(mdata);
+ break;
+ case BITBANG_CS_INACTIVE:
+ mtk_clear_pause_bit(mdata);
+ break;
+ }
+}
+
+static void mtk_spi_start_transfer(struct mtk_spi_ddata *mdata)
+{
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val |= 1 << SPI_CMD_ACT_OFFSET;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static void mtk_spi_resume_transfer(struct mtk_spi_ddata *mdata)
+{
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_RESUME_MASK;
+ reg_val |= 1 << SPI_CMD_RESUME_OFFSET;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static int mtk_spi_setup_packet(struct mtk_spi_ddata *mdata,
+ struct spi_transfer *xfer)
+{
+ struct device *dev = &mdata->bitbang.master->dev;
+ u32 packet_size, packet_loop, reg_val;
+
+ packet_size = min_t(unsigned, xfer->len, PACKET_SIZE);
+
+ /* mtk hw has the restriction that xfer len must be a multiple of 1024,
+ * when it is greater than 1024bytes.
+ */
+ if (xfer->len % packet_size) {
+ dev_err(dev, "ERROR!The lens must be a multiple of %d, your len %d\n",
+ PACKET_SIZE, xfer->len);
+ return -EINVAL;
+ }
+
+ packet_loop = xfer->len / packet_size;
+
+ reg_val = readl(mdata->base + SPI_CFG1_REG);
+ reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK + SPI_CFG1_PACKET_LOOP_MASK);
+ reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
+ reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
+ writel(reg_val, mdata->base + SPI_CFG1_REG);
+
+ return 0;
+}
+
+static int mtk_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *xfer)
+{
+ struct spi_master *master = spi->master;
+ struct mtk_spi_ddata *mdata = spi_master_get_devdata(master);
+ struct device *dev = &mdata->bitbang.master->dev;
+ int cmd, ret;
+
+ /* mtk spi hw tx/rx have 4bytes aligned restriction,
+ * so kmalloc tx/rx buffer to workaround here.
+ */
+ mdata->tx_buf = NULL;
+ mdata->rx_buf = NULL;
+ if (xfer->tx_buf) {
+ mdata->tx_buf = kmalloc(xfer->len, GFP_KERNEL);
+ if (!mdata->tx_buf) {
+ dev_err(dev, "malloc tx_buf failed.\n");
+ ret = -ENOMEM;
+ goto err_free;
+ }
+ memcpy((void *)mdata->tx_buf, xfer->tx_buf, xfer->len);
+ }
+ if (xfer->rx_buf) {
+ mdata->rx_buf = kmalloc(xfer->len, GFP_KERNEL);
+ if (!mdata->rx_buf) {
+ dev_err(dev, "malloc rx_buf failed.\n");
+ ret = -ENOMEM;
+ goto err_free;
+ }
+ }
+
+ reinit_completion(&mdata->done);
+
+ xfer->tx_dma = DMA_ERROR_CODE;
+ xfer->rx_dma = DMA_ERROR_CODE;
+ if (xfer->tx_buf) {
+ xfer->tx_dma = dma_map_single(dev, (void *)mdata->tx_buf,
+ xfer->len, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, xfer->tx_dma)) {
+ dev_err(dev, "dma mapping tx_buf error.\n");
+ ret = -ENOMEM;
+ goto err_free;
+ }
+ }
+ if (xfer->rx_buf) {
+ xfer->rx_dma = dma_map_single(dev, mdata->rx_buf,
+ xfer->len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, xfer->rx_dma)) {
+ if (xfer->tx_buf)
+ dma_unmap_single(dev, xfer->tx_dma,
+ xfer->len, DMA_TO_DEVICE);
+ dev_err(dev, "dma mapping rx_buf error.\n");
+ ret = -ENOMEM;
+ goto err_free;
+ }
+ }
+
+ ret = mtk_spi_setup_packet(mdata, xfer);
+ if (ret != 0)
+ goto err_free;
+
+ /* Here is mt8173 HW issue: RX must enable TX, then TX transfer
+ * dummy data; TX don't need to enable RX. so enable TX dma for
+ * RX to workaround.
+ */
+ cmd = readl(mdata->base + SPI_CMD_REG);
+ if (xfer->tx_buf || (mdata->platform_compat & COMPAT_MT8173))
+ cmd |= 1 << SPI_CMD_TX_DMA_OFFSET;
+ if (xfer->rx_buf)
+ cmd |= 1 << SPI_CMD_RX_DMA_OFFSET;
+ writel(cmd, mdata->base + SPI_CMD_REG);
+
+ /* set up the DMA bus address */
+ if (xfer->tx_dma != DMA_ERROR_CODE)
+ writel(cpu_to_le32(xfer->tx_dma), mdata->base + SPI_TX_SRC_REG);
+ if (xfer->rx_dma != DMA_ERROR_CODE)
+ writel(cpu_to_le32(xfer->rx_dma), mdata->base + SPI_RX_DST_REG);
+
+ if (mdata->state == IDLE)
+ mtk_spi_start_transfer(mdata);
+ else if (mdata->state == PAUSED)
+ mtk_spi_resume_transfer(mdata);
+ else
+ mdata->state = INPROGRESS;
+
+ wait_for_completion(&mdata->done);
+
+ if (xfer->tx_dma != DMA_ERROR_CODE) {
+ dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE);
+ xfer->tx_dma = DMA_ERROR_CODE;
+ }
+ if (xfer->rx_dma != DMA_ERROR_CODE) {
+ dma_unmap_single(dev, xfer->rx_dma, xfer->len, DMA_FROM_DEVICE);
+ xfer->rx_dma = DMA_ERROR_CODE;
+ }
+
+ /* spi disable dma */
+ cmd = readl(mdata->base + SPI_CMD_REG);
+ cmd &= ~SPI_CMD_TX_DMA_MASK;
+ cmd &= ~SPI_CMD_RX_DMA_MASK;
+ writel(cmd, mdata->base + SPI_CMD_REG);
+
+ if (xfer->rx_buf)
+ memcpy(xfer->rx_buf, mdata->rx_buf, xfer->len);
+
+ ret = xfer->len;
+
+err_free:
+ kfree(mdata->tx_buf);
+ kfree(mdata->rx_buf);
+ return ret;
+}
+
+static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
+{
+ struct mtk_spi_ddata *mdata = dev_id;
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_STATUS0_REG);
+ if (reg_val & 0x2)
+ mdata->state = PAUSED;
+ else
+ mdata->state = IDLE;
+ complete(&mdata->done);
+
+ return IRQ_HANDLED;
+}
+
+static unsigned long mtk_get_device_prop(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+
+ match = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
+ return (unsigned long)match->data;
+}
+
+static int mtk_spi_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct mtk_spi_ddata *mdata;
+ struct resource *res;
+ int ret;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(struct mtk_spi_ddata));
+ if (!master) {
+ dev_err(&pdev->dev, "failed to alloc spi master\n");
+ return -ENOMEM;
+ }
+
+ platform_set_drvdata(pdev, master);
+
+ master->dev.of_node = pdev->dev.of_node;
+ master->bus_num = pdev->id;
+ master->num_chipselect = 1;
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+
+ mdata = spi_master_get_devdata(master);
+
+ mdata->bitbang.master = master;
+ mdata->bitbang.chipselect = mtk_spi_chipselect;
+ mdata->bitbang.setup_transfer = mtk_spi_setup_transfer;
+ mdata->bitbang.txrx_bufs = mtk_spi_txrx_bufs;
+ mdata->platform_compat = mtk_get_device_prop(pdev);
+
+ if (mdata->platform_compat & COMPAT_MT8173) {
+ ret = of_property_read_u32(pdev->dev.of_node, "pad-select",
+ &mdata->pad_sel);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to read pad select: %d\n",
+ ret);
+ goto err;
+ }
+
+ if (mdata->pad_sel > MT8173_MAX_PAD_SEL) {
+ dev_err(&pdev->dev, "wrong pad-select: %u\n",
+ mdata->pad_sel);
+ goto err;
+ }
+ }
+
+ init_completion(&mdata->done);
+
+ mdata->clk = devm_clk_get(&pdev->dev, "main");
+ if (IS_ERR(mdata->clk)) {
+ ret = PTR_ERR(mdata->clk);
+ dev_err(&pdev->dev, "failed to get clock: %d\n", ret);
+ goto err;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "failed to determine base address\n");
+ goto err;
+ }
+
+ mdata->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mdata->base)) {
+ ret = PTR_ERR(mdata->base);
+ goto err;
+ }
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get irq (%d)\n", ret);
+ goto err;
+ }
+
+ mdata->irq = ret;
+
+ if (!pdev->dev.dma_mask)
+ pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
+
+ mdata->bitbang.master->dev.dma_mask = pdev->dev.dma_mask;
+
+ ret = clk_prepare_enable(mdata->clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable clock (%d)\n", ret);
+ goto err;
+ }
+
+ ret = devm_request_irq(&pdev->dev, mdata->irq, mtk_spi_interrupt,
+ IRQF_TRIGGER_NONE, dev_name(&pdev->dev), mdata);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
+ goto err_disable_clk;
+ }
+
+ ret = spi_bitbang_start(&mdata->bitbang);
+ if (ret) {
+ dev_err(&pdev->dev, "spi_bitbang_start failed (%d)\n", ret);
+err_disable_clk:
+ clk_disable_unprepare(mdata->clk);
+err:
+ spi_master_put(master);
+ }
+
+ return ret;
+}
+
+static int mtk_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct mtk_spi_ddata *mdata = spi_master_get_devdata(master);
+
+ spi_bitbang_stop(&mdata->bitbang);
+ mtk_spi_reset(mdata);
+ clk_disable_unprepare(mdata->clk);
+ spi_master_put(master);
+
+ return 0;
+}
+
+struct platform_driver mtk_spi_driver = {
+ .driver = {
+ .name = "mtk-spi",
+ .of_match_table = mtk_spi_of_match,
+ },
+ .probe = mtk_spi_probe,
+ .remove = mtk_spi_remove,
+};
+
+module_platform_driver(mtk_spi_driver);
+
+MODULE_DESCRIPTION("MTK SPI Controller driver");
+MODULE_AUTHOR("Leilk Liu <leilk.liu at mediatek.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform: mtk_spi");
--
1.8.1.1.dirty
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