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linux/drivers/spi/spi-mt65xx.c
Daniel Kurtz 1ce24864bf spi: mediatek: Only do dma for 4-byte aligned buffers 
Mediatek SPI DMA only works when tx and rx buffer addresses are 4-byte
aligned.

Unaligned DMA transactions appeared to work previously, since we the
spi core was incorrectly using the spi_master device for dma, which
had a 0 dma_mask, and therefore the swiotlb dma map operations were
falling back to using bounce buffers.  Since each DMA transaction would
use its own buffer, the mapped starting address of each transaction was
always aligned.  When doing real DMA, the mapped address will share the
alignment of the raw tx/rx buffer provided by the SPI user, which may or
may not be aligned.

If a buffer is not aligned, we cannot use DMA, and must use FIFO based
transaction instead.

So, this patch implements a scheme that allows using the FIFO for
arbitrary length transactions (larger than the 32-byte FIFO size) by
reloading the FIFO in the interrupt handler.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Cc: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-31 19:55:38 +00:00

809 lines
21 KiB
C
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/*
* 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>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_gpio.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 BIT(0)
#define SPI_CMD_RESUME BIT(1)
#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 MT8173_SPI_MAX_PAD_SEL 3
#define MTK_SPI_PAUSE_INT_STATUS 0x2
#define MTK_SPI_IDLE 0
#define MTK_SPI_PAUSED 1
#define MTK_SPI_MAX_FIFO_SIZE 32U
#define MTK_SPI_PACKET_SIZE 1024
struct mtk_spi_compatible {
bool need_pad_sel;
/* Must explicitly send dummy Tx bytes to do Rx only transfer */
bool must_tx;
};
struct mtk_spi {
void __iomem *base;
u32 state;
int pad_num;
u32 *pad_sel;
struct clk *parent_clk, *sel_clk, *spi_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 mtk_common_compat;
static const struct mtk_spi_compatible mt8173_compat = {
.need_pad_sel = true,
.must_tx = 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,
};
static const struct of_device_id mtk_spi_of_match[] = {
{ .compatible = "mediatek,mt2701-spi",
.data = (void *)&mtk_common_compat,
},
{ .compatible = "mediatek,mt6589-spi",
.data = (void *)&mtk_common_compat,
},
{ .compatible = "mediatek,mt8135-spi",
.data = (void *)&mtk_common_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 int mtk_spi_prepare_message(struct spi_master *master,
struct spi_message *msg)
{
u16 cpha, cpol;
u32 reg_val;
struct spi_device *spi = msg->spi;
struct mtk_chip_config *chip_config = spi->controller_data;
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);
if (cpha)
reg_val |= SPI_CMD_CPHA;
else
reg_val &= ~SPI_CMD_CPHA;
if (cpol)
reg_val |= SPI_CMD_CPOL;
else
reg_val &= ~SPI_CMD_CPOL;
/* set the mlsbx and mlsbtx */
if (chip_config->tx_mlsb)
reg_val |= SPI_CMD_TXMSBF;
else
reg_val &= ~SPI_CMD_TXMSBF;
if (chip_config->rx_mlsb)
reg_val |= SPI_CMD_RXMSBF;
else
reg_val &= ~SPI_CMD_RXMSBF;
/* set the tx/rx endian */
#ifdef __LITTLE_ENDIAN
reg_val &= ~SPI_CMD_TX_ENDIAN;
reg_val &= ~SPI_CMD_RX_ENDIAN;
#else
reg_val |= SPI_CMD_TX_ENDIAN;
reg_val |= SPI_CMD_RX_ENDIAN;
#endif
/* set finish and pause interrupt always enable */
reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
/* 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[spi->chip_select],
mdata->base + SPI_PAD_SEL_REG);
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;
writel(reg_val, mdata->base + SPI_CMD_REG);
} else {
reg_val &= ~SPI_CMD_PAUSE_EN;
writel(reg_val, mdata->base + SPI_CMD_REG);
mdata->state = MTK_SPI_IDLE;
mtk_spi_reset(mdata);
}
}
static void mtk_spi_prepare_transfer(struct spi_master *master,
struct spi_transfer *xfer)
{
u32 spi_clk_hz, div, sck_time, cs_time, 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;
sck_time = (div + 1) / 2;
cs_time = sck_time * 2;
reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_HIGH_OFFSET);
reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
reg_val |= (((cs_time - 1) & 0xff) << 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 |= (((cs_time - 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(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
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);
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);
}
static void mtk_spi_enable_transfer(struct spi_master *master)
{
u32 cmd;
struct mtk_spi *mdata = spi_master_get_devdata(master);
cmd = readl(mdata->base + SPI_CMD_REG);
if (mdata->state == MTK_SPI_IDLE)
cmd |= SPI_CMD_ACT;
else
cmd |= SPI_CMD_RESUME;
writel(cmd, mdata->base + SPI_CMD_REG);
}
static int mtk_spi_get_mult_delta(u32 xfer_len)
{
u32 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(xfer->tx_dma, mdata->base + SPI_TX_SRC_REG);
if (mdata->rx_sgl)
writel(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, remainder;
u32 reg_val;
struct mtk_spi *mdata = spi_master_get_devdata(master);
mdata->cur_transfer = xfer;
mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
mtk_spi_prepare_transfer(master, xfer);
mtk_spi_setup_packet(master);
cnt = xfer->len / 4;
iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
remainder = xfer->len % 4;
if (remainder > 0) {
reg_val = 0;
memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
writel(reg_val, 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)
{
/* Buffers for DMA transactions must be 4-byte aligned */
return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
(unsigned long)xfer->tx_buf % 4 == 0 &&
(unsigned long)xfer->rx_buf % 4 == 0);
}
static int mtk_spi_setup(struct spi_device *spi)
{
struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
if (!spi->controller_data)
spi->controller_data = (void *)&mtk_default_chip_info;
if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
return 0;
}
static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
{
u32 cmd, reg_val, cnt, remainder;
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 & MTK_SPI_PAUSE_INT_STATUS)
mdata->state = MTK_SPI_PAUSED;
else
mdata->state = MTK_SPI_IDLE;
if (!master->can_dma(master, master->cur_msg->spi, trans)) {
if (trans->rx_buf) {
cnt = mdata->xfer_len / 4;
ioread32_rep(mdata->base + SPI_RX_DATA_REG,
trans->rx_buf, cnt);
remainder = mdata->xfer_len % 4;
if (remainder > 0) {
reg_val = readl(mdata->base + SPI_RX_DATA_REG);
memcpy(trans->rx_buf + (cnt * 4),
&reg_val, remainder);
}
}
trans->len -= mdata->xfer_len;
if (!trans->len) {
spi_finalize_current_transfer(master);
return IRQ_HANDLED;
}
if (trans->tx_buf)
trans->tx_buf += mdata->xfer_len;
if (trans->rx_buf)
trans->rx_buf += mdata->xfer_len;
mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, trans->len);
mtk_spi_setup_packet(master);
cnt = trans->len / 4;
iowrite32_rep(mdata->base + SPI_TX_DATA_REG, trans->tx_buf, cnt);
remainder = trans->len % 4;
if (remainder > 0) {
reg_val = 0;
memcpy(&reg_val, trans->tx_buf + (cnt * 4), remainder);
writel(reg_val, mdata->base + SPI_TX_DATA_REG);
}
mtk_spi_enable_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 i, irq, ret;
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_message = mtk_spi_prepare_message;
master->transfer_one = mtk_spi_transfer_one;
master->can_dma = mtk_spi_can_dma;
master->setup = mtk_spi_setup;
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) {
mdata->pad_num = of_property_count_u32_elems(
pdev->dev.of_node,
"mediatek,pad-select");
if (mdata->pad_num < 0) {
dev_err(&pdev->dev,
"No 'mediatek,pad-select' property\n");
ret = -EINVAL;
goto err_put_master;
}
mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
sizeof(u32), GFP_KERNEL);
if (!mdata->pad_sel) {
ret = -ENOMEM;
goto err_put_master;
}
for (i = 0; i < mdata->pad_num; i++) {
of_property_read_u32_index(pdev->dev.of_node,
"mediatek,pad-select",
i, &mdata->pad_sel[i]);
if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
i, mdata->pad_sel[i]);
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->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;
}
mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
if (IS_ERR(mdata->sel_clk)) {
ret = PTR_ERR(mdata->sel_clk);
dev_err(&pdev->dev, "failed to get sel-clk: %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;
}
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->sel_clk, mdata->parent_clk);
if (ret < 0) {
dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
clk_disable_unprepare(mdata->spi_clk);
goto err_put_master;
}
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_disable_runtime_pm;
}
if (mdata->dev_comp->need_pad_sel) {
if (mdata->pad_num != master->num_chipselect) {
dev_err(&pdev->dev,
"pad_num does not match num_chipselect(%d != %d)\n",
mdata->pad_num, master->num_chipselect);
ret = -EINVAL;
goto err_disable_runtime_pm;
}
if (!master->cs_gpios && master->num_chipselect > 1) {
dev_err(&pdev->dev,
"cs_gpios not specified and num_chipselect > 1\n");
ret = -EINVAL;
goto err_disable_runtime_pm;
}
if (master->cs_gpios) {
for (i = 0; i < master->num_chipselect; i++) {
ret = devm_gpio_request(&pdev->dev,
master->cs_gpios[i],
dev_name(&pdev->dev));
if (ret) {
dev_err(&pdev->dev,
"can't get CS GPIO %i\n", i);
goto err_disable_runtime_pm;
}
}
}
}
return 0;
err_disable_runtime_pm:
pm_runtime_disable(&pdev->dev);
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);
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) {
dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
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);
int ret;
ret = clk_prepare_enable(mdata->spi_clk);
if (ret < 0) {
dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
return ret;
}
return 0;
}
#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)
};
static 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 <leilk.liu@mediatek.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:mtk-spi");
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