From 047222cfefe97ef8706f03117bc8deada4cb4ddd Mon Sep 17 00:00:00 2001 From: Leilk Liu Date: Fri, 8 May 2015 16:55:42 +0800 Subject: [PATCH 26/76] spi: mediatek: Add spi bus for Mediatek MT8173 This patch adds basic spi bus for MT8173. Signed-off-by: Leilk Liu --- 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 72b0590..53dbea3 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -325,6 +325,16 @@ 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 + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 "); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform: mtk_spi"); -- 1.7.10.4