[PATCH v4] mmc: moxart: fix probe logic
From: Jonas Jensen <hidden>
Date: 2015-02-03 15:55:54
Also in:
linux-mmc
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Ulf Hansson, Linus Torvalds
From: Arnd Bergmann <arnd@arndb.de>
Jonas Jensen wanted to submit a patch for these, but apparently
forgot about it. I stumbled over this symptom first:
drivers/built-in.o: In function `moxart_probe':
:(.text+0x2af128): undefined reference to `of_dma_request_slave_channel'
This is because of_dma_request_slave_channel is an internal helper
and not exported to loadable module. I'm changing the driver to
use dma_request_slave_channel_reason() instead.
Further problems from inspection:
* The remove function must not call kfree on the host pointer,
because it is allocated together with the mmc_host.
* The clock is never released
* The dma_cap_mask_t is completely unused and can be removed
* deferred probing does not work if the dma driver is loaded
after the mmc driver.
This patch should fix all of the above.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jonas Jensen <redacted>
---
Notes:
This is a forward of Arnd's v2 patch.
v2: do not call clk_put() on an error pointer
v3: fix NULL dereference on host->clk
v4: rework to use devm_clk_get()
Applies to next-20150113
drivers/mmc/host/moxart-mmc.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c
index d2a1ef6..6cb4053 100644
--- a/drivers/mmc/host/moxart-mmc.c
+++ b/drivers/mmc/host/moxart-mmc.c@@ -17,6 +17,7 @@ #include <linux/init.h> #include <linux/platform_device.h> #include <linux/delay.h> +#include <linux/errno.h> #include <linux/interrupt.h> #include <linux/blkdev.h> #include <linux/dma-mapping.h>
@@ -562,7 +563,6 @@ static int moxart_probe(struct platform_device *pdev) struct dma_slave_config cfg; struct clk *clk; void __iomem *reg_mmc; - dma_cap_mask_t mask; int irq, ret; u32 i;
@@ -586,9 +586,9 @@ static int moxart_probe(struct platform_device *pdev) goto out; } - clk = of_clk_get(node, 0); + clk = devm_clk_get(dev, 0); if (IS_ERR(clk)) { - dev_err(dev, "of_clk_get failed\n"); + dev_err(dev, "devm_clk_get failed\n"); ret = PTR_ERR(clk); goto out; }
@@ -603,9 +603,6 @@ static int moxart_probe(struct platform_device *pdev) if (ret) goto out; - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - host = mmc_priv(mmc); host->mmc = mmc; host->base = reg_mmc;
@@ -613,8 +610,8 @@ static int moxart_probe(struct platform_device *pdev) host->timeout = msecs_to_jiffies(1000); host->sysclk = clk_get_rate(clk); host->fifo_width = readl(host->base + REG_FEATURE) << 2; - host->dma_chan_tx = of_dma_request_slave_channel(node, "tx"); - host->dma_chan_rx = of_dma_request_slave_channel(node, "rx"); + host->dma_chan_tx = dma_request_slave_channel_reason(dev, "tx"); + host->dma_chan_rx = dma_request_slave_channel_reason(dev, "rx"); spin_lock_init(&host->lock);
@@ -624,6 +621,11 @@ static int moxart_probe(struct platform_device *pdev) mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */ if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) { + if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER || + PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto out; + } dev_dbg(dev, "PIO mode transfer enabled\n"); host->have_dma = false; } else {
@@ -702,9 +704,6 @@ static int moxart_remove(struct platform_device *pdev) writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, host->base + REG_CLOCK_CONTROL); } - - kfree(host); - return 0; }
--
1.8.2.1