[PATCH] spi: mediatek: fix spi incorrect endian usage and remove redundant clock
From: Leilk Liu
Date: Tue Aug 18 2015 - 06:54:38 EST
This patch fixes incorrect endian usage, removes redundant
clock in prepare_hardware/unprepare_hardware and revises
coding styles.
Signed-off-by: Leilk Liu <leilk.liu@xxxxxxxxxxxx>
---
Change in this patch:
1. fix incorrect endian usage on big-endian system.
2. delete redundant clock in prepare/unprepare_hardware.
3. revise coding styles.
---
drivers/spi/spi-mt65xx.c | 163 +++++++++++++------------------
include/linux/platform_data/spi-mt65xx.h | 2 -
2 files changed, 69 insertions(+), 96 deletions(-)
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 519f50c..a9da887 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -16,6 +16,7 @@
#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>
@@ -48,15 +49,8 @@
#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
-
+#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)
@@ -71,12 +65,10 @@
#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_PAUSE_INT_STATUS 0x2
+
#define MTK_SPI_IDLE 0
#define MTK_SPI_PAUSED 1
@@ -84,8 +76,9 @@
#define MTK_SPI_PACKET_SIZE 1024
struct mtk_spi_compatible {
- u32 need_pad_sel;
- u32 must_tx;
+ bool need_pad_sel;
+ /* Must explicitly send dummy Tx bytes to do Rx only transfer */
+ bool must_tx;
};
struct mtk_spi {
@@ -100,19 +93,11 @@ struct mtk_spi {
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,
-};
-
+static const struct mtk_spi_compatible mt6589_compat;
+static const struct mtk_spi_compatible mt8135_compat;
static const struct mtk_spi_compatible mt8173_compat = {
- .need_pad_sel = MTK_SPI_QUIRK_PAD_SELECT,
- .must_tx = MTK_SPI_QUIRK_MUST_TX,
+ .need_pad_sel = true,
+ .must_tx = true,
};
/*
@@ -122,8 +107,6 @@ static const struct mtk_spi_compatible mt8173_compat = {
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[] = {
@@ -156,14 +139,23 @@ static void mtk_spi_config(struct mtk_spi *mdata,
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);
+ 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 */
- 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);
+#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_EN;
@@ -186,30 +178,14 @@ 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) {
+ if (!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;
}
@@ -226,9 +202,14 @@ static int mtk_spi_prepare_message(struct spi_master *master,
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);
+ 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;
writel(reg_val, mdata->base + SPI_CMD_REG);
chip_config = spi->controller_data;
@@ -257,8 +238,7 @@ static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
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;
+ 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);
@@ -267,21 +247,18 @@ static void mtk_spi_prepare_transfer(struct spi_master *master,
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;
+ sck_time = (div + 1) / 2;
+ cs_time = sck_time * 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);
+ 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_idletime - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
+ reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
writel(reg_val, mdata->base + SPI_CFG1_REG);
}
@@ -290,11 +267,11 @@ 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);
+ 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 &= ~(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);
@@ -302,20 +279,20 @@ static void mtk_spi_setup_packet(struct spi_master *master)
static void mtk_spi_enable_transfer(struct spi_master *master)
{
- int cmd;
+ 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 |= 1 << SPI_CMD_ACT_OFFSET;
+ cmd |= SPI_CMD_ACT;
else
- cmd |= 1 << SPI_CMD_RESUME_OFFSET;
+ cmd |= SPI_CMD_RESUME;
writel(cmd, mdata->base + SPI_CMD_REG);
}
-static int mtk_spi_get_mult_delta(int xfer_len)
+static int mtk_spi_get_mult_delta(u32 xfer_len)
{
- int mult_delta;
+ u32 mult_delta;
if (xfer_len > MTK_SPI_PACKET_SIZE)
mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
@@ -368,7 +345,7 @@ static int mtk_spi_fifo_transfer(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
- int cnt, i;
+ int cnt;
struct mtk_spi *mdata = spi_master_get_devdata(master);
mdata->cur_transfer = xfer;
@@ -380,10 +357,7 @@ static int mtk_spi_fifo_transfer(struct spi_master *master,
cnt = xfer->len / 4 + 1;
else
cnt = xfer->len / 4;
-
- for (i = 0; i < cnt; i++)
- writel(*((u32 *)xfer->tx_buf + i),
- mdata->base + SPI_TX_DATA_REG);
+ iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
mtk_spi_enable_transfer(master);
@@ -453,30 +427,25 @@ static bool mtk_spi_can_dma(struct spi_master *master,
static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
{
- u32 cmd, reg_val, i;
+ u32 cmd, reg_val, cnt;
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)
+ 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)) {
- /* 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);
- *((u8 *)(trans->rx_buf + i)) =
- (reg_val >> ((i % 4) * 8)) & 0xff;
- }
+ if (mdata->xfer_len % 4)
+ cnt = mdata->xfer_len / 4 + 1;
+ else
+ cnt = mdata->xfer_len / 4;
+ ioread32_rep(mdata->base + SPI_RX_DATA_REG,
+ trans->rx_buf, cnt);
}
spi_finalize_current_transfer(master);
return IRQ_HANDLED;
@@ -541,7 +510,6 @@ static int mtk_spi_probe(struct platform_device *pdev)
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;
@@ -694,6 +662,7 @@ static int mtk_spi_resume(struct device *dev)
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;
}
@@ -720,8 +689,14 @@ 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 clk_prepare_enable(mdata->spi_clk);
+ return 0;
}
#endif /* CONFIG_PM */
diff --git a/include/linux/platform_data/spi-mt65xx.h b/include/linux/platform_data/spi-mt65xx.h
index 7512255..54b0448 100644
--- a/include/linux/platform_data/spi-mt65xx.h
+++ b/include/linux/platform_data/spi-mt65xx.h
@@ -16,7 +16,5 @@
struct mtk_chip_config {
u32 tx_mlsb;
u32 rx_mlsb;
- u32 tx_endian;
- u32 rx_endian;
};
#endif
--
1.8.1.1.dirty
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