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-rw-r--r--drivers/spi/spi-bcm63xx-hsspi.c109
1 files changed, 98 insertions, 11 deletions
diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c
index a65a0ec67641..55cbe7deba08 100644
--- a/drivers/spi/spi-bcm63xx-hsspi.c
+++ b/drivers/spi/spi-bcm63xx-hsspi.c
@@ -57,6 +57,7 @@
#define PINGPONG_CMD_SS_SHIFT 12
#define HSSPI_PINGPONG_STATUS_REG(x) (0x84 + (x) * 0x40)
+#define HSSPI_PINGPONG_STATUS_SRC_BUSY BIT(1)
#define HSSPI_PROFILE_CLK_CTRL_REG(x) (0x100 + (x) * 0x20)
#define CLK_CTRL_FREQ_CTRL_MASK 0x0000ffff
@@ -96,11 +97,16 @@
#define HSSPI_SPI_MAX_CS 8
#define HSSPI_BUS_NUM 1 /* 0 is legacy SPI */
+#define HSSPI_POLL_STATUS_TIMEOUT_MS 100
+
+#define HSSPI_WAIT_MODE_POLLING 0
+#define HSSPI_WAIT_MODE_INTR 1
+#define HSSPI_WAIT_MODE_MAX HSSPI_WAIT_MODE_INTR
struct bcm63xx_hsspi {
struct completion done;
struct mutex bus_mutex;
-
+ struct mutex msg_mutex;
struct platform_device *pdev;
struct clk *clk;
struct clk *pll_clk;
@@ -109,6 +115,52 @@ struct bcm63xx_hsspi {
u32 speed_hz;
u8 cs_polarity;
+ u32 wait_mode;
+};
+
+static ssize_t wait_mode_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct spi_controller *ctrl = dev_get_drvdata(dev);
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(ctrl);
+
+ return sprintf(buf, "%d\n", bs->wait_mode);
+}
+
+static ssize_t wait_mode_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct spi_controller *ctrl = dev_get_drvdata(dev);
+ struct bcm63xx_hsspi *bs = spi_master_get_devdata(ctrl);
+ u32 val;
+
+ if (kstrtou32(buf, 10, &val))
+ return -EINVAL;
+
+ if (val > HSSPI_WAIT_MODE_MAX) {
+ dev_warn(dev, "invalid wait mode %u\n", val);
+ return -EINVAL;
+ }
+
+ mutex_lock(&bs->msg_mutex);
+ bs->wait_mode = val;
+ /* clear interrupt status to avoid spurious int on next transfer */
+ if (val == HSSPI_WAIT_MODE_INTR)
+ __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
+ mutex_unlock(&bs->msg_mutex);
+
+ return count;
+}
+
+static DEVICE_ATTR_RW(wait_mode);
+
+static struct attribute *bcm63xx_hsspi_attrs[] = {
+ &dev_attr_wait_mode.attr,
+ NULL,
+};
+
+static const struct attribute_group bcm63xx_hsspi_group = {
+ .attrs = bcm63xx_hsspi_attrs,
};
static void bcm63xx_hsspi_set_cs(struct bcm63xx_hsspi *bs, unsigned int cs,
@@ -163,6 +215,8 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
int step_size = HSSPI_BUFFER_LEN;
const u8 *tx = t->tx_buf;
u8 *rx = t->rx_buf;
+ u32 val;
+ unsigned long limit;
bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz);
bcm63xx_hsspi_set_cs(bs, spi->chip_select, true);
@@ -197,8 +251,9 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
__raw_writew((u16)cpu_to_be16(opcode | curr_step), bs->fifo);
/* enable interrupt */
- __raw_writel(HSSPI_PINGx_CMD_DONE(0),
- bs->regs + HSSPI_INT_MASK_REG);
+ if (bs->wait_mode == HSSPI_WAIT_MODE_INTR)
+ __raw_writel(HSSPI_PINGx_CMD_DONE(0),
+ bs->regs + HSSPI_INT_MASK_REG);
/* start the transfer */
__raw_writel(!chip_select << PINGPONG_CMD_SS_SHIFT |
@@ -206,9 +261,21 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
PINGPONG_COMMAND_START_NOW,
bs->regs + HSSPI_PINGPONG_COMMAND_REG(0));
- if (wait_for_completion_timeout(&bs->done, HZ) == 0) {
- dev_err(&bs->pdev->dev, "transfer timed out!\n");
- return -ETIMEDOUT;
+ if (bs->wait_mode == HSSPI_WAIT_MODE_INTR) {
+ if (wait_for_completion_timeout(&bs->done, HZ) == 0)
+ goto err_timeout;
+ } else {
+ /* polling mode checks for status busy bit */
+ limit = jiffies + msecs_to_jiffies(HSSPI_POLL_STATUS_TIMEOUT_MS);
+ while (!time_after(jiffies, limit)) {
+ val = __raw_readl(bs->regs + HSSPI_PINGPONG_STATUS_REG(0));
+ if (val & HSSPI_PINGPONG_STATUS_SRC_BUSY)
+ cpu_relax();
+ else
+ break;
+ }
+ if (val & HSSPI_PINGPONG_STATUS_SRC_BUSY)
+ goto err_timeout;
}
if (rx) {
@@ -220,6 +287,10 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
}
return 0;
+
+err_timeout:
+ dev_err(&bs->pdev->dev, "transfer timed out!\n");
+ return -ETIMEDOUT;
}
static int bcm63xx_hsspi_setup(struct spi_device *spi)
@@ -269,6 +340,7 @@ static int bcm63xx_hsspi_transfer_one(struct spi_master *master,
int dummy_cs;
u32 reg;
+ mutex_lock(&bs->msg_mutex);
/* This controller does not support keeping CS active during idle.
* To work around this, we use the following ugly hack:
*
@@ -306,6 +378,7 @@ static int bcm63xx_hsspi_transfer_one(struct spi_master *master,
__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
mutex_unlock(&bs->bus_mutex);
+ mutex_unlock(&bs->msg_mutex);
msg->status = status;
spi_finalize_current_message(master);
@@ -398,8 +471,10 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
bs->regs = regs;
bs->speed_hz = rate;
bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0));
+ bs->wait_mode = HSSPI_WAIT_MODE_POLLING;
mutex_init(&bs->bus_mutex);
+ mutex_init(&bs->msg_mutex);
init_completion(&bs->done);
master->dev.of_node = dev->of_node;
@@ -434,21 +509,32 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
__raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF,
bs->regs + HSSPI_GLOBAL_CTRL_REG);
- ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED,
- pdev->name, bs);
+ if (irq > 0) {
+ ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED,
+ pdev->name, bs);
- if (ret)
- goto out_put_master;
+ if (ret)
+ goto out_put_master;
+ }
pm_runtime_enable(&pdev->dev);
+ if (sysfs_create_group(&pdev->dev.kobj, &bcm63xx_hsspi_group)) {
+ dev_err(&pdev->dev, "couldn't register sysfs group\n");
+ goto out_pm_disable;
+ }
+
/* register and we are done */
ret = devm_spi_register_master(dev, master);
if (ret)
- goto out_pm_disable;
+ goto out_sysgroup_disable;
+
+ dev_info(dev, "Broadcom 63XX High Speed SPI Controller driver");
return 0;
+out_sysgroup_disable:
+ sysfs_remove_group(&pdev->dev.kobj, &bcm63xx_hsspi_group);
out_pm_disable:
pm_runtime_disable(&pdev->dev);
out_put_master:
@@ -470,6 +556,7 @@ static int bcm63xx_hsspi_remove(struct platform_device *pdev)
__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
clk_disable_unprepare(bs->pll_clk);
clk_disable_unprepare(bs->clk);
+ sysfs_remove_group(&pdev->dev.kobj, &bcm63xx_hsspi_group);
return 0;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-28 07:09:11 +0300