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spi: spi-zynqmp-gqspi: fix clk_enable/disable imbalance issue

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The clks "pclk" and "ref_clk" are enabled twice during the probe. The
first time is in the function zynqmp_qspi_probe and the second time is
in zynqmp_qspi_setup_op which is called by devm_spi_register_controller.
Then calling zynqmp_qspi_remove (rmmod this module) to disable these clks
will trigger a warning as below:

[  309.124604] Unpreparing enabled qspi_ref
[  309.128641] WARNING: CPU: 1 PID: 537 at drivers/clk/clk.c:824 clk_core_unprepare+0x108/0x110

Since pm_runtime works now, clks can be enabled/disabled by calling
zynqmp_runtime_suspend/resume. So we don't need to enable these clks
explicitly in zynqmp_qspi_setup_op. Remove them to fix this issue.

And remove clk enabling/disabling in zynqmp_qspi_resume because there is
no spi transfer operation so enabling ref_clk is redundant meanwhile pclk
is not disabled for it is shared with other peripherals.

Furthermore replace clk_enable/disable with clk_prepare_enable and
clk_disable_unprepare in runtime_suspend/resume functions.

Fixes: 1c26372e5a ("spi: spi-zynqmp-gqspi: Update driver to use spi-mem framework")
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Link: https://lore.kernel.org/r/20210416004652.2975446-2-quanyang.wang@windriver.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Quanyang Wang 2021-04-16 08:46:48 +08:00 committed by Mark Brown
parent c7ed5fd5fb
commit c6bdae0801
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0
1 changed files with 8 additions and 39 deletions
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47
drivers/spi/spi-zynqmp-gqspi.c
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@ -487,24 +487,10 @@ static int zynqmp_qspi_setup_op(struct spi_device *qspi)
{
struct spi_controller *ctlr = qspi->master;
struct zynqmp_qspi *xqspi = spi_controller_get_devdata(ctlr);
struct device *dev = &ctlr->dev;
int ret;
if (ctlr->busy)
return -EBUSY;
ret = clk_enable(xqspi->refclk);
if (ret) {
dev_err(dev, "Cannot enable device clock.\n");
return ret;
}
ret = clk_enable(xqspi->pclk);
if (ret) {
dev_err(dev, "Cannot enable APB clock.\n");
clk_disable(xqspi->refclk);
return ret;
}
zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
return 0;
@ -863,26 +849,9 @@ static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
{
struct spi_controller *ctlr = dev_get_drvdata(dev);
struct zynqmp_qspi *xqspi = spi_controller_get_devdata(ctlr);
int ret = 0;
ret = clk_enable(xqspi->pclk);
if (ret) {
dev_err(dev, "Cannot enable APB clock.\n");
return ret;
}
ret = clk_enable(xqspi->refclk);
if (ret) {
dev_err(dev, "Cannot enable device clock.\n");
clk_disable(xqspi->pclk);
return ret;
}
spi_controller_resume(ctlr);
clk_disable(xqspi->refclk);
clk_disable(xqspi->pclk);
return 0;
}
@ -898,8 +867,8 @@ static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
{
struct zynqmp_qspi *xqspi = (struct zynqmp_qspi *)dev_get_drvdata(dev);
clk_disable(xqspi->refclk);
clk_disable(xqspi->pclk);
clk_disable_unprepare(xqspi->refclk);
clk_disable_unprepare(xqspi->pclk);
return 0;
}
@ -917,16 +886,16 @@ static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
struct zynqmp_qspi *xqspi = (struct zynqmp_qspi *)dev_get_drvdata(dev);
int ret;
ret = clk_enable(xqspi->pclk);
ret = clk_prepare_enable(xqspi->pclk);
if (ret) {
dev_err(dev, "Cannot enable APB clock.\n");
return ret;
}
ret = clk_enable(xqspi->refclk);
ret = clk_prepare_enable(xqspi->refclk);
if (ret) {
dev_err(dev, "Cannot enable device clock.\n");
clk_disable(xqspi->pclk);
clk_disable_unprepare(xqspi->pclk);
return ret;
}
@ -1136,13 +1105,11 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
goto remove_master;
}
init_completion(&xqspi->data_completion);
xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
if (IS_ERR(xqspi->refclk)) {
dev_err(dev, "ref_clk clock not found.\n");
ret = PTR_ERR(xqspi->refclk);
goto clk_dis_pclk;
goto remove_master;
}
ret = clk_prepare_enable(xqspi->pclk);
@ -1157,6 +1124,8 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
goto clk_dis_pclk;
}
init_completion(&xqspi->data_completion);
mutex_init(&xqspi->op_lock);
pm_runtime_use_autosuspend(&pdev->dev);