[PATCH v3] mmc: pxamci: fix the device-tree probe deferral path

From: Robert Jarzmik
Date: Mon Feb 08 2016 - 09:18:09 EST


When the gpio driver is probed after the mmc one, the read/write gpio
and card detection one return -EPROBE_DEFER. Unfortunately, the memory
region remains requested, and upon the next probe, the probe will fail
anyway with -EBUSY.

Fix this by releasing the memory resource upon probe failure.

More broadly, this patch uses devm_*() primitives whenever possible in
the probe function.

Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
---
Since v1: broaden the devm_*() enveloppe
Since v2: further broaden devm_*(): regulator + clock
---
drivers/mmc/host/pxamci.c | 35 +++++++++--------------------------
1 file changed, 9 insertions(+), 26 deletions(-)

diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 28a057fae0a1..da824772bbb4 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -86,7 +86,7 @@ struct pxamci_host {
static inline void pxamci_init_ocr(struct pxamci_host *host)
{
#ifdef CONFIG_REGULATOR
- host->vcc = regulator_get_optional(mmc_dev(host->mmc), "vmmc");
+ host->vcc = devm_regulator_get_optional(mmc_dev(host->mmc), "vmmc");

if (IS_ERR(host->vcc))
host->vcc = NULL;
@@ -654,12 +654,8 @@ static int pxamci_probe(struct platform_device *pdev)

r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
- if (!r || irq < 0)
- return -ENXIO;
-
- r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
- if (!r)
- return -EBUSY;
+ if (irq < 0)
+ return irq;

mmc = mmc_alloc_host(sizeof(struct pxamci_host), &pdev->dev);
if (!mmc) {
@@ -695,7 +691,7 @@ static int pxamci_probe(struct platform_device *pdev)
host->pdata = pdev->dev.platform_data;
host->clkrt = CLKRT_OFF;

- host->clk = clk_get(&pdev->dev, NULL);
+ host->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(host->clk)) {
ret = PTR_ERR(host->clk);
host->clk = NULL;
@@ -727,9 +723,9 @@ static int pxamci_probe(struct platform_device *pdev)
host->irq = irq;
host->imask = MMC_I_MASK_ALL;

- host->base = ioremap(r->start, SZ_4K);
- if (!host->base) {
- ret = -ENOMEM;
+ host->base = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(host->base)) {
+ ret = PTR_ERR(host->base);
goto out;
}

@@ -742,7 +738,8 @@ static int pxamci_probe(struct platform_device *pdev)
writel(64, host->base + MMC_RESTO);
writel(host->imask, host->base + MMC_I_MASK);

- ret = request_irq(host->irq, pxamci_irq, 0, DRIVER_NAME, host);
+ ret = devm_request_irq(&pdev->dev, host->irq, pxamci_irq, 0,
+ DRIVER_NAME, host);
if (ret)
goto out;

@@ -833,14 +830,9 @@ out:
dma_release_channel(host->dma_chan_rx);
if (host->dma_chan_tx)
dma_release_channel(host->dma_chan_tx);
- if (host->base)
- iounmap(host->base);
- if (host->clk)
- clk_put(host->clk);
}
if (mmc)
mmc_free_host(mmc);
- release_resource(r);
return ret;
}

@@ -859,9 +851,6 @@ static int pxamci_remove(struct platform_device *pdev)
gpio_ro = host->pdata->gpio_card_ro;
gpio_power = host->pdata->gpio_power;
}
- if (host->vcc)
- regulator_put(host->vcc);
-
if (host->pdata && host->pdata->exit)
host->pdata->exit(&pdev->dev, mmc);

@@ -870,16 +859,10 @@ static int pxamci_remove(struct platform_device *pdev)
END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
host->base + MMC_I_MASK);

- free_irq(host->irq, host);
dmaengine_terminate_all(host->dma_chan_rx);
dmaengine_terminate_all(host->dma_chan_tx);
dma_release_channel(host->dma_chan_rx);
dma_release_channel(host->dma_chan_tx);
- iounmap(host->base);
-
- clk_put(host->clk);
-
- release_resource(host->res);

mmc_free_host(mmc);
}
--
2.1.4