Re: [v5,2/3] spi: mediatek: Add spi bus for Mediatek MT8173
From: Nicolas Boichat <hidden>
Date: 2015-08-11 10:52:26
Also in:
linux-arm-kernel, linux-mediatek, linux-spi, lkml
Hi Leilk, On Fri, Aug 7, 2015 at 3:19 PM, [off-list ref] wrote:
quoted hunk ↗ jump to hunk
This patch adds basic spi bus for MT8173. Signed-off-by: Leilk Liu <redacted> --- Change in this patch: 1. change "pad-select" to "mediatek,pad-select". 2. modify clk relevant implement. --- drivers/spi/Kconfig | 9 + drivers/spi/Makefile | 1 + drivers/spi/spi-mt65xx.c | 749 +++++++++++++++++++++++++++++++ include/linux/platform_data/spi-mt65xx.h | 22 + 4 files changed, 781 insertions(+) create mode 100644 drivers/spi/spi-mt65xx.c create mode 100644 include/linux/platform_data/spi-mt65xx.hdiff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 0cae169..38ddfba 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig@@ -326,6 +326,15 @@ 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 + 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 and MT81XX series ARM SoCs. + config SPI_OC_TINY tristate "OpenCores tiny SPI" depends on GPIOLIB || COMPILE_TESTdiff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 1154dba..9746beb2 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.odiff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c new file mode 100644 index 0000000..4676b01 --- /dev/null +++ b/drivers/spi/spi-mt65xx.c@@ -0,0 +1,749 @@ +/* + * Copyright (c) 2015 MediaTek Inc. + * Author: Leilk Liu <leilk.liu@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/clk.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h>
Since you are using readl/writel, please import linux/io.h as well (it is implicitly imported by spi/spi.h, but better be safe...)
+#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/platform_data/spi-mt65xx.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.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_TX_DATA_REG 0x0010 +#define SPI_RX_DATA_REG 0x0014 +#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_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_CMD_ACT_OFFSET 0 +#define SPI_CMD_RESUME_OFFSET 1 +#define SPI_CMD_CPHA_OFFSET 8 +#define SPI_CMD_CPOL_OFFSET 9 +#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
It feels error-prone that you are defining these offsets here, then redefining the bits just below. Looking at the code, I think it's better if you remove these SPI_CMD_*_OFFSET defines, and only use the BIT(x) defines below.
+#define SPI_CMD_RST BIT(2)
+#define SPI_CMD_PAUSE_EN BIT(4)
+#define SPI_CMD_DEASSERT BIT(5)
+#define SPI_CMD_CPHA BIT(8)
+#define SPI_CMD_CPOL BIT(9)
+#define SPI_CMD_RX_DMA BIT(10)
+#define SPI_CMD_TX_DMA BIT(11)
+#define SPI_CMD_TXMSBF BIT(12)
+#define SPI_CMD_RXMSBF BIT(13)
+#define SPI_CMD_RX_ENDIAN BIT(14)
+#define SPI_CMD_TX_ENDIAN BIT(15)
+#define SPI_CMD_FINISH_IE BIT(16)
+#define SPI_CMD_PAUSE_IE BIT(17)
+
+#define MTK_SPI_QUIRK_PAD_SELECT 1
+/* Must explicitly send dummy Tx bytes to do Rx only transfer */
+#define MTK_SPI_QUIRK_MUST_TX 1
+
+#define MT8173_SPI_MAX_PAD_SEL 3
+
+#define MTK_SPI_IDLE 0
+#define MTK_SPI_PAUSED 1
+
+#define MTK_SPI_MAX_FIFO_SIZE 32
+#define MTK_SPI_PACKET_SIZE 1024
+
+struct mtk_spi_compatible {
+ u32 need_pad_sel;
+ u32 must_tx;Since the quirks are true/false, define these as bool, and remove MTK_SPI_QUIRK_PAD_SELECT/MTK_SPI_QUIRK_MUST_TX. Move the comment here too.
+};
+
+struct mtk_spi {
+ void __iomem *base;
+ u32 state;
+ u32 pad_sel;
+ struct clk *spi_clk, *parent_clk;
+ struct spi_transfer *cur_transfer;
+ u32 xfer_len;
+ struct scatterlist *tx_sgl, *rx_sgl;
+ u32 tx_sgl_len, rx_sgl_len;
+ const struct mtk_spi_compatible *dev_comp;
+};
+
+static const struct mtk_spi_compatible mt6589_compat = {
+ .need_pad_sel = 0,
+ .must_tx = 0,
+};
+
+static const struct mtk_spi_compatible mt8135_compat = {
+ .need_pad_sel = 0,
+ .must_tx = 0,
+};You don't need to set these explicitly to 0/false.
+
+static const struct mtk_spi_compatible mt8173_compat = {
+ .need_pad_sel = MTK_SPI_QUIRK_PAD_SELECT,
+ .must_tx = MTK_SPI_QUIRK_MUST_TX,Then you can set those as "true".
+};
+
+/*
+ * A piece of default chip info unless the platform
+ * supplies it.
+ */
+static const struct mtk_chip_config mtk_default_chip_info = {
+ .rx_mlsb = 1,
+ .tx_mlsb = 1,
+ .tx_endian = 0,
+ .rx_endian = 0,
+};
+
+static const struct of_device_id mtk_spi_of_match[] = {
+ { .compatible = "mediatek,mt6589-spi", .data = (void *)&mt6589_compat },
+ { .compatible = "mediatek,mt8135-spi", .data = (void *)&mt8135_compat },
+ { .compatible = "mediatek,mt8173-spi", .data = (void *)&mt8173_compat },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
+
+static void mtk_spi_reset(struct mtk_spi *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;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~SPI_CMD_RST;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static void mtk_spi_config(struct mtk_spi *mdata,
+ struct mtk_chip_config *chip_config)
+{
+ u32 reg_val;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+
+ /* set the mlsbx and mlsbtx */
+ reg_val &= ~(SPI_CMD_TXMSBF | SPI_CMD_RXMSBF);
+ reg_val |= (chip_config->tx_mlsb << SPI_CMD_TXMSBF_OFFSET);
+ reg_val |= (chip_config->rx_mlsb << SPI_CMD_RXMSBF_OFFSET);
+
+ /* set the tx/rx endian */
+ reg_val &= ~(SPI_CMD_TX_ENDIAN | SPI_CMD_RX_ENDIAN);
+ reg_val |= (chip_config->tx_endian << SPI_CMD_TX_ENDIAN_OFFSET);
+ reg_val |= (chip_config->rx_endian << SPI_CMD_RX_ENDIAN_OFFSET);
+
+ /* set finish and pause interrupt always enable */
+ reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_EN;
+
+ /* disable dma mode */
+ reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
+
+ /* disable deassert mode */
+ reg_val &= ~SPI_CMD_DEASSERT;
+
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ /* pad select */
+ if (mdata->dev_comp->need_pad_sel)
+ writel(mdata->pad_sel, mdata->base + SPI_PAD_SEL_REG);
+}
+
+static int mtk_spi_prepare_hardware(struct spi_master *master)
+{
+ struct spi_transfer *trans;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+ struct spi_message *msg = master->cur_msg;
+ int ret;
+
+ ret = clk_prepare_enable(mdata->spi_clk);
+ if (ret < 0) {
+ dev_err(&master->dev, "failed to enable clock (%d)\n", ret);
+ return ret;
+ }
+
+ trans = list_first_entry(&msg->transfers, struct spi_transfer,
+ transfer_list);
+ if (trans->cs_change == 0) {!trans->cs_change
+ mdata->state = MTK_SPI_IDLE;
+ mtk_spi_reset(mdata);
+ }
+
+ return ret;
+}
+
+static int mtk_spi_unprepare_hardware(struct spi_master *master)
+{
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ clk_disable_unprepare(mdata->spi_clk);
+
+ return 0;
+}In this case, prepare_hardware/unprepare_hardware is redundant with pm_runtime (apart from the cs_change check, possibly). If PM_RUNTIME is disabled, leave the clock enabled all the time, if not enable/disable in pm_runtime functions (as you already do) See https://git.kernel.org/cgit/linux/kernel/git/broonie/spi.git/commit/?id=db91841b58f9ad0ecbb81ed0fa496c3a1b67fd63 "spi/omap100k: Convert to runtime PM" for an example (it's one of the last driver that used prepare/unprepare calls, and got converted to pm_runtime)
+static int mtk_spi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ u32 reg_val;
+ u8 cpha, cpol;
+ struct mtk_chip_config *chip_config;
+ struct spi_device *spi = msg->spi;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ cpha = spi->mode & SPI_CPHA ? 1 : 0;
+ cpol = spi->mode & SPI_CPOL ? 1 : 0;
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ reg_val &= ~(SPI_CMD_CPHA | SPI_CMD_CPOL);
+ reg_val |= (cpha << SPI_CMD_CPHA_OFFSET);
+ reg_val |= (cpol << SPI_CMD_CPOL_OFFSET);This can actually be simplified a bit by using SPI_CMD_CPHA/SPI_CMD_CPOL instead.
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+
+ chip_config = spi->controller_data;
+ if (!chip_config) {
+ chip_config = (void *)&mtk_default_chip_info;
+ spi->controller_data = chip_config;
+ }
+ mtk_spi_config(mdata, chip_config);
+
+ return 0;
+}
+
+static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ u32 reg_val;
+ struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
+
+ reg_val = readl(mdata->base + SPI_CMD_REG);
+ if (!enable)
+ reg_val |= SPI_CMD_PAUSE_EN;
+ else
+ reg_val &= ~SPI_CMD_PAUSE_EN;
+ writel(reg_val, mdata->base + SPI_CMD_REG);
+}
+
+static void mtk_spi_prepare_transfer(struct spi_master *master,
+ struct spi_transfer *xfer)
+{
+ u32 spi_clk_hz, div, high_time, low_time, holdtime,
+ setuptime, cs_idletime, reg_val = 0;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ spi_clk_hz = clk_get_rate(mdata->spi_clk);
+ if (xfer->speed_hz < spi_clk_hz / 2)
+ div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz);
+ else
+ div = 1;
+
+ high_time = (div + 1) / 2;
+ low_time = (div + 1) / 2;
+ holdtime = (div + 1) / 2 * 2;
+ setuptime = (div + 1) / 2 * 2;
+ cs_idletime = (div + 1) / 2 * 2;Why setting variables with the exact same value? Can you do with just 2?
+ reg_val |= (((high_time - 1) & 0xff) << SPI_CFG0_SCK_HIGH_OFFSET); + reg_val |= (((low_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET); + reg_val |= (((holdtime - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET); + reg_val |= (((setuptime - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
Not sure of the details, but can you guarantee this will never overflow? I.e. can div be larger than 256?
+ 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 |= (((cs_idletime - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG1_REG);
+}
+
+static void mtk_spi_setup_packet(struct spi_master *master)
+{
+ u32 packet_size, packet_loop, reg_val;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ packet_size = min_t(unsigned, mdata->xfer_len, MTK_SPI_PACKET_SIZE);u32 instead of unsigned.
+ packet_loop = mdata->xfer_len / packet_size; + + reg_val = readl(mdata->base + SPI_CFG1_REG); + reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK + SPI_CFG1_PACKET_LOOP_MASK);
Use |, not +.
+ reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET; + reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
Can packet_loop be >256?
+ writel(reg_val, mdata->base + SPI_CFG1_REG);
+}
+
+static void mtk_spi_enable_transfer(struct spi_master *master)
+{
+ int cmd;u32
+ struct mtk_spi *mdata = spi_master_get_devdata(master); + + cmd = readl(mdata->base + SPI_CMD_REG); + if (mdata->state == MTK_SPI_IDLE) + cmd |= 1 << SPI_CMD_ACT_OFFSET; + else + cmd |= 1 << SPI_CMD_RESUME_OFFSET; + writel(cmd, mdata->base + SPI_CMD_REG); +} + +static int mtk_spi_get_mult_delta(int xfer_len)
xfer_len is a u32, so should be mult_delta.
+{
+ int mult_delta;
+
+ if (xfer_len > MTK_SPI_PACKET_SIZE)
+ mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
+ else
+ mult_delta = 0;
+
+ return mult_delta;
+}
+
+static void mtk_spi_update_mdata_len(struct spi_master *master)
+{
+ int mult_delta;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
+ if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
+ mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
+ mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
+ mdata->rx_sgl_len = mult_delta;
+ mdata->tx_sgl_len -= mdata->xfer_len;
+ } else {
+ mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
+ mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
+ mdata->tx_sgl_len = mult_delta;
+ mdata->rx_sgl_len -= mdata->xfer_len;
+ }
+ } else if (mdata->tx_sgl_len) {
+ mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
+ mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
+ mdata->tx_sgl_len = mult_delta;
+ } else if (mdata->rx_sgl_len) {
+ mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
+ mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
+ mdata->rx_sgl_len = mult_delta;
+ }
+}
+
+static void mtk_spi_setup_dma_addr(struct spi_master *master,
+ struct spi_transfer *xfer)
+{
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ if (mdata->tx_sgl)
+ writel(cpu_to_le32(xfer->tx_dma), mdata->base + SPI_TX_SRC_REG);
+ if (mdata->rx_sgl)
+ writel(cpu_to_le32(xfer->rx_dma), mdata->base + SPI_RX_DST_REG);
+}
+
+static int mtk_spi_fifo_transfer(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ int cnt, i;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ mdata->cur_transfer = xfer;
+ mdata->xfer_len = xfer->len;
+ mtk_spi_prepare_transfer(master, xfer);
+ mtk_spi_setup_packet(master);
+
+ if (xfer->len % 4)
+ cnt = xfer->len / 4 + 1;
+ else
+ cnt = xfer->len / 4;
+
+ for (i = 0; i < cnt; i++)
+ writel(*((u32 *)xfer->tx_buf + i),This will access past the end of tx_buf if len%4 > 0.
+ mdata->base + SPI_TX_DATA_REG);
+
+ mtk_spi_enable_transfer(master);
+
+ return 1;
+}
+
+static int mtk_spi_dma_transfer(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ int cmd;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+
+ mdata->tx_sgl = NULL;
+ mdata->rx_sgl = NULL;
+ mdata->tx_sgl_len = 0;
+ mdata->rx_sgl_len = 0;
+ mdata->cur_transfer = xfer;
+
+ mtk_spi_prepare_transfer(master, xfer);
+
+ cmd = readl(mdata->base + SPI_CMD_REG);
+ if (xfer->tx_buf)
+ cmd |= SPI_CMD_TX_DMA;
+ if (xfer->rx_buf)
+ cmd |= SPI_CMD_RX_DMA;
+ writel(cmd, mdata->base + SPI_CMD_REG);
+
+ if (xfer->tx_buf)
+ mdata->tx_sgl = xfer->tx_sg.sgl;
+ if (xfer->rx_buf)
+ mdata->rx_sgl = xfer->rx_sg.sgl;
+
+ if (mdata->tx_sgl) {
+ xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
+ mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
+ }
+ if (mdata->rx_sgl) {
+ xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
+ mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
+ }
+
+ mtk_spi_update_mdata_len(master);
+ mtk_spi_setup_packet(master);
+ mtk_spi_setup_dma_addr(master, xfer);
+ mtk_spi_enable_transfer(master);
+
+ return 1;
+}
+
+static int mtk_spi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ if (master->can_dma(master, spi, xfer))
+ return mtk_spi_dma_transfer(master, spi, xfer);
+ else
+ return mtk_spi_fifo_transfer(master, spi, xfer);
+}
+
+static bool mtk_spi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ return xfer->len > MTK_SPI_MAX_FIFO_SIZE;
+}
+
+static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
+{
+ u32 cmd, reg_val, i;
+ struct spi_master *master = dev_id;
+ struct mtk_spi *mdata = spi_master_get_devdata(master);
+ struct spi_transfer *trans = mdata->cur_transfer;
+
+ reg_val = readl(mdata->base + SPI_STATUS0_REG);
+ if (reg_val & 0x2)define 0x2?
+ mdata->state = MTK_SPI_PAUSED;
+ else
+ mdata->state = MTK_SPI_IDLE;
+
+ if (!master->can_dma(master, master->cur_msg->spi, trans)) {
+ /* xfer len is not N*4 bytes every time in a transfer,
+ * but SPI_RX_DATA_REG must reads 4 bytes once,
+ * so rx buffer byte by byte.
+ */
+ if (trans->rx_buf) {
+ for (i = 0; i < mdata->xfer_len; i++) {
+ if (i % 4 == 0)
+ reg_val =
+ readl(mdata->base + SPI_RX_DATA_REG);Strange indentation. Might be better to put readl on the same line, and SPI_RX_DATA_REG on the next one.
+ *((u8 *)(trans->rx_buf + i)) = + (reg_val >> ((i % 4) * 8)) & 0xff;
This feels a bit awkward... Also, & 0xff is not needed.
+ }
+ }
+ spi_finalize_current_transfer(master);
+ return IRQ_HANDLED;
+ }
+
+ if (mdata->tx_sgl)
+ trans->tx_dma += mdata->xfer_len;
+ if (mdata->rx_sgl)
+ trans->rx_dma += mdata->xfer_len;
+
+ if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
+ mdata->tx_sgl = sg_next(mdata->tx_sgl);
+ if (mdata->tx_sgl) {
+ trans->tx_dma = sg_dma_address(mdata->tx_sgl);
+ mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
+ }
+ }
+ if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
+ mdata->rx_sgl = sg_next(mdata->rx_sgl);
+ if (mdata->rx_sgl) {
+ trans->rx_dma = sg_dma_address(mdata->rx_sgl);
+ mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
+ }
+ }
+
+ if (!mdata->tx_sgl && !mdata->rx_sgl) {
+ /* spi disable dma */
+ cmd = readl(mdata->base + SPI_CMD_REG);
+ cmd &= ~SPI_CMD_TX_DMA;
+ cmd &= ~SPI_CMD_RX_DMA;
+ writel(cmd, mdata->base + SPI_CMD_REG);
+
+ spi_finalize_current_transfer(master);
+ return IRQ_HANDLED;
+ }
+
+ mtk_spi_update_mdata_len(master);
+ mtk_spi_setup_packet(master);
+ mtk_spi_setup_dma_addr(master, trans);
+ mtk_spi_enable_transfer(master);
+
+ return IRQ_HANDLED;
+}
+
+static int mtk_spi_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct mtk_spi *mdata;
+ const struct of_device_id *of_id;
+ struct resource *res;
+ int irq, ret;Space, not tab, between int and irq.
quoted hunk ↗ jump to hunk
+ + master = spi_alloc_master(&pdev->dev, sizeof(*mdata)); + if (!master) { + dev_err(&pdev->dev, "failed to alloc spi master\n"); + return -ENOMEM; + } + + master->auto_runtime_pm = true; + master->dev.of_node = pdev->dev.of_node; + master->mode_bits = SPI_CPOL | SPI_CPHA; + + master->set_cs = mtk_spi_set_cs; + master->prepare_transfer_hardware = mtk_spi_prepare_hardware; + master->unprepare_transfer_hardware = mtk_spi_unprepare_hardware; + master->prepare_message = mtk_spi_prepare_message; + master->transfer_one = mtk_spi_transfer_one; + master->can_dma = mtk_spi_can_dma; + + of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node); + if (!of_id) { + dev_err(&pdev->dev, "failed to probe of_node\n"); + ret = -EINVAL; + goto err_put_master; + } + + mdata = spi_master_get_devdata(master); + mdata->dev_comp = of_id->data; + if (mdata->dev_comp->must_tx) + master->flags = SPI_MASTER_MUST_TX; + + if (mdata->dev_comp->need_pad_sel) { + ret = of_property_read_u32(pdev->dev.of_node, + "mediatek,pad-select", + &mdata->pad_sel); + if (ret) { + dev_err(&pdev->dev, "failed to read pad select: %d\n", + ret); + goto err_put_master; + } + + if (mdata->pad_sel > MT8173_SPI_MAX_PAD_SEL) { + dev_err(&pdev->dev, "wrong pad-select: %u\n", + mdata->pad_sel); + ret = -EINVAL; + goto err_put_master; + } + } + + platform_set_drvdata(pdev, master); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENODEV; + dev_err(&pdev->dev, "failed to determine base address\n"); + goto err_put_master; + } + + mdata->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(mdata->base)) { + ret = PTR_ERR(mdata->base); + goto err_put_master; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "failed to get irq (%d)\n", irq); + ret = irq; + goto err_put_master; + } + + if (!pdev->dev.dma_mask) + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; + + ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt, + IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master); + if (ret) { + dev_err(&pdev->dev, "failed to register irq (%d)\n", ret); + goto err_put_master; + } + + mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk"); + if (IS_ERR(mdata->spi_clk)) { + ret = PTR_ERR(mdata->spi_clk); + dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret); + goto err_put_master; + } + + mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk"); + if (IS_ERR(mdata->parent_clk)) { + ret = PTR_ERR(mdata->parent_clk); + dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret); + goto err_put_master; + } + + ret = clk_prepare_enable(mdata->spi_clk); + if (ret < 0) { + dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret); + goto err_put_master; + } + + ret = clk_set_parent(mdata->spi_clk, mdata->parent_clk); + if (ret < 0) { + dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret); + goto err_disable_clk; + } + + clk_disable_unprepare(mdata->spi_clk); + + pm_runtime_enable(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "failed to register master (%d)\n", ret); + goto err_put_master; + } + + return 0; + +err_disable_clk: + clk_disable_unprepare(mdata->spi_clk); +err_put_master: + 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 *mdata = spi_master_get_devdata(master); + + pm_runtime_disable(&pdev->dev); + + mtk_spi_reset(mdata); + clk_disable_unprepare(mdata->spi_clk); + spi_master_put(master); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int mtk_spi_suspend(struct device *dev) +{ + int ret; + struct spi_master *master = dev_get_drvdata(dev); + struct mtk_spi *mdata = spi_master_get_devdata(master); + + ret = spi_master_suspend(master); + if (ret) + return ret; + + if (!pm_runtime_suspended(dev)) + clk_disable_unprepare(mdata->spi_clk); + + return ret; +} + +static int mtk_spi_resume(struct device *dev) +{ + int ret; + struct spi_master *master = dev_get_drvdata(dev); + struct mtk_spi *mdata = spi_master_get_devdata(master); + + if (!pm_runtime_suspended(dev)) { + ret = clk_prepare_enable(mdata->spi_clk); + if (ret < 0) + return ret; + } + + ret = spi_master_resume(master); + if (ret < 0) + clk_disable_unprepare(mdata->spi_clk); + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int mtk_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mtk_spi *mdata = spi_master_get_devdata(master); + + clk_disable_unprepare(mdata->spi_clk); + + return 0; +} + +static int mtk_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct mtk_spi *mdata = spi_master_get_devdata(master); + + return clk_prepare_enable(mdata->spi_clk); +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops mtk_spi_pm = { + SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume) + SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend, + mtk_spi_runtime_resume, NULL) +}; + +struct platform_driver mtk_spi_driver = { + .driver = { + .name = "mtk-spi", + .pm = &mtk_spi_pm, + .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 [off-list ref]"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform: mtk_spi");diff --git a/include/linux/platform_data/spi-mt65xx.h b/include/linux/platform_data/spi-mt65xx.h new file mode 100644 index 0000000..7512255 --- /dev/null +++ b/include/linux/platform_data/spi-mt65xx.h@@ -0,0 +1,22 @@ +/* + * MTK SPI bus driver definitions + * + * Copyright (c) 2015 MediaTek Inc. + * Author: Leilk Liu <leilk.liu@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. + */ + +#ifndef ____LINUX_PLATFORM_DATA_SPI_MTK_H +#define ____LINUX_PLATFORM_DATA_SPI_MTK_H + +/* Board specific platform_data */ +struct mtk_chip_config { + u32 tx_mlsb; + u32 rx_mlsb; + u32 tx_endian; + u32 rx_endian; +}; +#endif