[PATCH] spi: tegra114: reset controller on probe

From: Sowjanya Komatineni
Date: Wed Mar 27 2019 - 01:56:32 EST


Fixes: SPI driver can be built as module so perform SPI controller reset
on probe to make sure it is in valid state before initiating transfer.

Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-tegra114.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
index 05bb2f9bff3c..09cfae3abce2 100644
--- a/drivers/spi/spi-tegra114.c
+++ b/drivers/spi/spi-tegra114.c
@@ -1136,27 +1136,19 @@ static int tegra_spi_probe(struct platform_device *pdev)

spi_irq = platform_get_irq(pdev, 0);
tspi->irq = spi_irq;
- ret = request_threaded_irq(tspi->irq, tegra_spi_isr,
- tegra_spi_isr_thread, IRQF_ONESHOT,
- dev_name(&pdev->dev), tspi);
- if (ret < 0) {
- dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
- tspi->irq);
- goto exit_free_master;
- }

tspi->clk = devm_clk_get(&pdev->dev, "spi");
if (IS_ERR(tspi->clk)) {
dev_err(&pdev->dev, "can not get clock\n");
ret = PTR_ERR(tspi->clk);
- goto exit_free_irq;
+ goto exit_free_master;
}

tspi->rst = devm_reset_control_get_exclusive(&pdev->dev, "spi");
if (IS_ERR(tspi->rst)) {
dev_err(&pdev->dev, "can not get reset\n");
ret = PTR_ERR(tspi->rst);
- goto exit_free_irq;
+ goto exit_free_master;
}

tspi->max_buf_size = SPI_FIFO_DEPTH << 2;
@@ -1164,7 +1156,7 @@ static int tegra_spi_probe(struct platform_device *pdev)

ret = tegra_spi_init_dma_param(tspi, true);
if (ret < 0)
- goto exit_free_irq;
+ goto exit_free_master;
ret = tegra_spi_init_dma_param(tspi, false);
if (ret < 0)
goto exit_rx_dma_free;
@@ -1186,18 +1178,32 @@ static int tegra_spi_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
goto exit_pm_disable;
}
+
+ reset_control_assert(tspi->rst);
+ udelay(2);
+ reset_control_deassert(tspi->rst);
tspi->def_command1_reg = SPI_M_S;
tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1);
pm_runtime_put(&pdev->dev);
+ ret = request_threaded_irq(tspi->irq, tegra_spi_isr,
+ tegra_spi_isr_thread, IRQF_ONESHOT,
+ dev_name(&pdev->dev), tspi);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
+ tspi->irq);
+ goto exit_pm_disable;
+ }

master->dev.of_node = pdev->dev.of_node;
ret = devm_spi_register_master(&pdev->dev, master);
if (ret < 0) {
dev_err(&pdev->dev, "can not register to master err %d\n", ret);
- goto exit_pm_disable;
+ goto exit_free_irq;
}
return ret;

+exit_free_irq:
+ free_irq(spi_irq, tspi);
exit_pm_disable:
pm_runtime_disable(&pdev->dev);
if (!pm_runtime_status_suspended(&pdev->dev))
@@ -1205,8 +1211,6 @@ static int tegra_spi_probe(struct platform_device *pdev)
tegra_spi_deinit_dma_param(tspi, false);
exit_rx_dma_free:
tegra_spi_deinit_dma_param(tspi, true);
-exit_free_irq:
- free_irq(spi_irq, tspi);
exit_free_master:
spi_master_put(master);
return ret;
--
2.20.1