[PATCH] mmc: moxart: fix probe logic
From: arnd@arndb.de (Arnd Bergmann)
Date: 2015-01-29 16:15:31
Also in:
linux-mmc
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Ulf Hansson, Linus Torvalds
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> --- Jonas, can you check this patch and provide an Ack if it's ok?
diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c
index d2a1ef61ec97..d9401a1cc589 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>
@@ -131,6 +132,7 @@ struct moxart_host { struct mmc_host *mmc; struct mmc_request *mrq; struct scatterlist *cur_sg; + struct clk *clk; struct completion dma_complete; struct completion pio_complete;
@@ -560,9 +562,7 @@ static int moxart_probe(struct platform_device *pdev) struct mmc_host *mmc; struct moxart_host *host = NULL; struct dma_slave_config cfg; - struct clk *clk; void __iomem *reg_mmc; - dma_cap_mask_t mask; int irq, ret; u32 i;
@@ -586,10 +586,10 @@ static int moxart_probe(struct platform_device *pdev) goto out; } - clk = of_clk_get(node, 0); - if (IS_ERR(clk)) { + host->clk = of_clk_get(node, 0); + if (IS_ERR(host->clk)) { dev_err(dev, "of_clk_get failed\n"); - ret = PTR_ERR(clk); + ret = PTR_ERR(host->clk); goto out; }
@@ -603,18 +603,15 @@ 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; host->reg_phys = res_mmc.start; host->timeout = msecs_to_jiffies(1000); - host->sysclk = clk_get_rate(clk); + host->sysclk = clk_get_rate(host->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 {
@@ -677,6 +679,8 @@ static int moxart_probe(struct platform_device *pdev) return 0; out: + if (host->clk) + clk_put(host->clk); if (mmc) mmc_free_host(mmc); return ret;
@@ -694,6 +698,7 @@ static int moxart_remove(struct platform_device *pdev) dma_release_channel(host->dma_chan_tx); if (!IS_ERR(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); + clk_put(host->clk); mmc_remove_host(mmc); mmc_free_host(mmc);
@@ -702,9 +707,6 @@ 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; }