[PATCH v3] spi: stm32-qspi: Update spi registering

From: patrice.chotard
Date: Mon Jan 17 2022 - 07:18:11 EST


From: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>

Some device driver need to communicate to qspi device during the remove
process, qspi controller must be functional when spi_unregister_master()
is called.

To ensure this, replace devm_spi_register_master() by spi_register_master()
and spi_unregister_master() is called directly in .remove callback before
stopping the qspi controller.

This issue was put in evidence using kernel v5.11 and later
with a spi-nor which supports the software reset feature introduced
by commit d73ee7534cc5 ("mtd: spi-nor: core: perform a Soft Reset on
shutdown")

Fixes: c530cd1d9d5e ("spi: spi-mem: add stm32 qspi controller")

Signed-off-by: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # 5.8.x
---

v3:
_ Update error path due to devm_spi_alloc_master() usage

v2:
_ update commit message
_ make usage of devm_spi_alloc_master() instead of spi_alloc_master()

drivers/spi/spi-stm32-qspi.c | 47 +++++++++++++-----------------------
1 file changed, 17 insertions(+), 30 deletions(-)

diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
index 514337c86d2c..ffdc55f87e82 100644
--- a/drivers/spi/spi-stm32-qspi.c
+++ b/drivers/spi/spi-stm32-qspi.c
@@ -688,7 +688,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
struct resource *res;
int ret, irq;

- ctrl = spi_alloc_master(dev, sizeof(*qspi));
+ ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
if (!ctrl)
return -ENOMEM;

@@ -697,58 +697,46 @@ static int stm32_qspi_probe(struct platform_device *pdev)

res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
qspi->io_base = devm_ioremap_resource(dev, res);
- if (IS_ERR(qspi->io_base)) {
- ret = PTR_ERR(qspi->io_base);
- goto err_master_put;
- }
+ if (IS_ERR(qspi->io_base))
+ return PTR_ERR(qspi->io_base);

qspi->phys_base = res->start;

res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
qspi->mm_base = devm_ioremap_resource(dev, res);
- if (IS_ERR(qspi->mm_base)) {
- ret = PTR_ERR(qspi->mm_base);
- goto err_master_put;
- }
+ if (IS_ERR(qspi->mm_base))
+ return PTR_ERR(qspi->mm_base);

qspi->mm_size = resource_size(res);
- if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ) {
- ret = -EINVAL;
- goto err_master_put;
- }
+ if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ)
+ return -EINVAL;

irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- ret = irq;
- goto err_master_put;
- }
+ if (irq < 0)
+ return irq;

ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
dev_name(dev), qspi);
if (ret) {
dev_err(dev, "failed to request irq\n");
- goto err_master_put;
+ return ret;
}

init_completion(&qspi->data_completion);
init_completion(&qspi->match_completion);

qspi->clk = devm_clk_get(dev, NULL);
- if (IS_ERR(qspi->clk)) {
- ret = PTR_ERR(qspi->clk);
- goto err_master_put;
- }
+ if (IS_ERR(qspi->clk))
+ return PTR_ERR(qspi->clk);

qspi->clk_rate = clk_get_rate(qspi->clk);
- if (!qspi->clk_rate) {
- ret = -EINVAL;
- goto err_master_put;
- }
+ if (!qspi->clk_rate)
+ return -EINVAL;

ret = clk_prepare_enable(qspi->clk);
if (ret) {
dev_err(dev, "can not enable the clock\n");
- goto err_master_put;
+ return ret;
}

rstc = devm_reset_control_get_exclusive(dev, NULL);
@@ -784,7 +772,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
pm_runtime_enable(dev);
pm_runtime_get_noresume(dev);

- ret = devm_spi_register_master(dev, ctrl);
+ ret = spi_register_master(ctrl);
if (ret)
goto err_pm_runtime_free;

@@ -806,8 +794,6 @@ static int stm32_qspi_probe(struct platform_device *pdev)
stm32_qspi_dma_free(qspi);
err_clk_disable:
clk_disable_unprepare(qspi->clk);
-err_master_put:
- spi_master_put(qspi->ctrl);

return ret;
}
@@ -817,6 +803,7 @@ static int stm32_qspi_remove(struct platform_device *pdev)
struct stm32_qspi *qspi = platform_get_drvdata(pdev);

pm_runtime_get_sync(qspi->dev);
+ spi_unregister_master(qspi->ctrl);
/* disable qspi */
writel_relaxed(0, qspi->io_base + QSPI_CR);
stm32_qspi_dma_free(qspi);
--
2.17.1