[PATCH 1/8] mmc: sdhci-of-aspeed: Fix sdhci software reset can't be cleared issue.

[Cool Lee]

> > Replace sdhci software reset by scu reset from top.
> >
> > Signed-off-by: Cool Lee <cool_lee at aspeedtech.com>
> > ---
> >  drivers/mmc/host/sdhci-of-aspeed.c | 55
> > +++++++++++++++++++++++++++++-
> >  1 file changed, 54 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-of-aspeed.c
> > b/drivers/mmc/host/sdhci-of-aspeed.c
> > index d6de010551b9..01bc574272eb 100644
> > --- a/drivers/mmc/host/sdhci-of-aspeed.c
> > +++ b/drivers/mmc/host/sdhci-of-aspeed.c
> > @@ -13,6 +13,7 @@
> >  #include <linux/of.h>
> >  #include <linux/of_platform.h>
> >  #include <linux/platform_device.h>
> > +#include <linux/reset.h>
> >  #include <linux/spinlock.h>
> >
> >  #include "sdhci-pltfm.h"
> > @@ -39,6 +40,7 @@
> >  struct aspeed_sdc {
> >  	struct clk *clk;
> >  	struct resource *res;
> > +	struct reset_control *rst;
> >
> >  	spinlock_t lock;
> >  	void __iomem *regs;
> > @@ -328,13 +330,58 @@ static u32 aspeed_sdhci_readl(struct sdhci_host
> *host, int reg)
> >  	return val;
> >  }
> >
> > +static void aspeed_sdhci_reset(struct sdhci_host *host, u8 mask) {
> > +	struct sdhci_pltfm_host *pltfm_priv;
> > +	struct aspeed_sdhci *aspeed_sdhci;
> > +	struct aspeed_sdc *aspeed_sdc;
> > +	u32 save_array[7];
> > +	u32 reg_array[] = {SDHCI_DMA_ADDRESS,
> > +			SDHCI_BLOCK_SIZE,
> > +			SDHCI_ARGUMENT,
> > +			SDHCI_HOST_CONTROL,
> > +			SDHCI_CLOCK_CONTROL,
> > +			SDHCI_INT_ENABLE,
> > +			SDHCI_SIGNAL_ENABLE};
> > +	int i;
> > +	u16 tran_mode;
> > +	u32 mmc8_mode;
> > +
> > +	pltfm_priv = sdhci_priv(host);
> > +	aspeed_sdhci = sdhci_pltfm_priv(pltfm_priv);
> > +	aspeed_sdc = aspeed_sdhci->parent;
> > +
> > +	if (!IS_ERR(aspeed_sdc->rst)) {
> > +		for (i = 0; i < ARRAY_SIZE(reg_array); i++)
> > +			save_array[i] = sdhci_readl(host, reg_array[i]);
> > +
> > +		tran_mode = sdhci_readw(host, SDHCI_TRANSFER_MODE);
> > +		mmc8_mode = readl(aspeed_sdc->regs);
> > +
> > +		reset_control_assert(aspeed_sdc->rst);
> > +		mdelay(1);
> > +		reset_control_deassert(aspeed_sdc->rst);
> > +		mdelay(1);
> 
> Why are there delays here ...
Ok, I will remove from here. From hardware's perspective, the delay is not needed.

> 
> [...]
> > @@ -535,6 +582,12 @@ static int aspeed_sdc_probe(struct
> > platform_device *pdev)
> >
> >  	spin_lock_init(&sdc->lock);
> >
> > +	sdc->rst = devm_reset_control_get(&pdev->dev, NULL);
> > +	if (!IS_ERR(sdc->rst)) {
> > +		reset_control_assert(sdc->rst);
> > +		reset_control_deassert(sdc->rst);
> 
> ... but not here?
> 
> regards
> Philipp