diff mbox series

[RFC,v3.1,18/27] mmc: sdhci-uhs2: add clock operations

Message ID 20201106022726.19831-19-takahiro.akashi@linaro.org (mailing list archive)
State New, archived
Headers show
Series Add support UHS-II for GL9755 | expand

Commit Message

AKASHI Takahiro Nov. 6, 2020, 2:27 a.m. UTC 
This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.

Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 drivers/mmc/host/sdhci-uhs2.c | 41 +++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

Comments

Adrian Hunter Nov. 26, 2020, 8:17 a.m. UTC | #1 
On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.
> 
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
>  drivers/mmc/host/sdhci-uhs2.c | 41 +++++++++++++++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 994dff967e85..55362ace1857 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -11,6 +11,7 @@
>   */
>  
>  #include <linux/delay.h>
> +#include <linux/ktime.h>
>  #include <linux/module.h>
>  
>  #include "sdhci.h"
> @@ -385,6 +386,42 @@ void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>  	__sdhci_uhs2_set_ios(mmc, ios);
>  }
>  
> +static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> +{
> +        struct sdhci_host *host = mmc_priv(mmc);
> +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +
> +	clk &= ~SDHCI_CLOCK_CARD_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +}
> +
> +static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> +{
> +        struct sdhci_host *host = mmc_priv(mmc);
> +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +	ktime_t timeout;
> +
> +	clk |= SDHCI_CLOCK_CARD_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +
> +	/* Wait max 20 ms */
> +	timeout = ktime_add_ms(ktime_get(), 20);
> +	while (1) {
> +		bool timedout = ktime_after(ktime_get(), timeout);
> +
> +		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);

Can use read_poll_timeout(sdhci_readw,..., host, SDHCI_CLOCK_CONTROL)

> +		if (clk & SDHCI_CLOCK_INT_STABLE)
> +			break;
> +		if (timedout) {
> +			pr_err("%s: Internal clock never stabilised.\n",
> +			       mmc_hostname(host->mmc));
> +			sdhci_dumpregs(host);
> +			return;
> +		}
> +		udelay(10);
> +	}
> +}
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * Driver init/exit                                                          *
> @@ -556,6 +593,10 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
>  
>  	if (!host->mmc_host_ops.uhs2_detect_init)
>  		host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
> +	if (!host->mmc_host_ops.uhs2_disable_clk)
> +		host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> +	if (!host->mmc_host_ops.uhs2_enable_clk)
> +		host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
>  
>  	return 0;
>  }
>
AKASHI Takahiro Dec. 1, 2020, 2:27 a.m. UTC | #2 
On Thu, Nov 26, 2020 at 10:17:59AM +0200, Adrian Hunter wrote:
> On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> > This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.
> > 
> > Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > ---
> >  drivers/mmc/host/sdhci-uhs2.c | 41 +++++++++++++++++++++++++++++++++++
> >  1 file changed, 41 insertions(+)
> > 
> > diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> > index 994dff967e85..55362ace1857 100644
> > --- a/drivers/mmc/host/sdhci-uhs2.c
> > +++ b/drivers/mmc/host/sdhci-uhs2.c
> > @@ -11,6 +11,7 @@
> >   */
> >  
> >  #include <linux/delay.h>
> > +#include <linux/ktime.h>
> >  #include <linux/module.h>
> >  
> >  #include "sdhci.h"
> > @@ -385,6 +386,42 @@ void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> >  	__sdhci_uhs2_set_ios(mmc, ios);
> >  }
> >  
> > +static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> > +{
> > +        struct sdhci_host *host = mmc_priv(mmc);
> > +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > +
> > +	clk &= ~SDHCI_CLOCK_CARD_EN;
> > +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +}
> > +
> > +static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> > +{
> > +        struct sdhci_host *host = mmc_priv(mmc);
> > +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > +	ktime_t timeout;
> > +
> > +	clk |= SDHCI_CLOCK_CARD_EN;
> > +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +
> > +	/* Wait max 20 ms */
> > +	timeout = ktime_add_ms(ktime_get(), 20);
> > +	while (1) {
> > +		bool timedout = ktime_after(ktime_get(), timeout);
> > +
> > +		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> 
> Can use read_poll_timeout(sdhci_readw,..., host, SDHCI_CLOCK_CONTROL)

Okay.

-Takahiro Akashi

> > +		if (clk & SDHCI_CLOCK_INT_STABLE)
> > +			break;
> > +		if (timedout) {
> > +			pr_err("%s: Internal clock never stabilised.\n",
> > +			       mmc_hostname(host->mmc));
> > +			sdhci_dumpregs(host);
> > +			return;
> > +		}
> > +		udelay(10);
> > +	}
> > +}
> > +
> >  /*****************************************************************************\
> >   *                                                                           *
> >   * Driver init/exit                                                          *
> > @@ -556,6 +593,10 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
> >  
> >  	if (!host->mmc_host_ops.uhs2_detect_init)
> >  		host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
> > +	if (!host->mmc_host_ops.uhs2_disable_clk)
> > +		host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> > +	if (!host->mmc_host_ops.uhs2_enable_clk)
> > +		host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
> >  
> >  	return 0;
> >  }
> > 
>
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index 994dff967e85..55362ace1857 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -11,6 +11,7 @@ 
  */
 
 #include <linux/delay.h>
+#include <linux/ktime.h>
 #include <linux/module.h>
 
 #include "sdhci.h"
@@ -385,6 +386,42 @@  void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	__sdhci_uhs2_set_ios(mmc, ios);
 }
 
+static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
+{
+        struct sdhci_host *host = mmc_priv(mmc);
+	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+
+	clk &= ~SDHCI_CLOCK_CARD_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+}
+
+static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
+{
+        struct sdhci_host *host = mmc_priv(mmc);
+	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+	ktime_t timeout;
+
+	clk |= SDHCI_CLOCK_CARD_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+	/* Wait max 20 ms */
+	timeout = ktime_add_ms(ktime_get(), 20);
+	while (1) {
+		bool timedout = ktime_after(ktime_get(), timeout);
+
+		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+		if (clk & SDHCI_CLOCK_INT_STABLE)
+			break;
+		if (timedout) {
+			pr_err("%s: Internal clock never stabilised.\n",
+			       mmc_hostname(host->mmc));
+			sdhci_dumpregs(host);
+			return;
+		}
+		udelay(10);
+	}
+}
+
 /*****************************************************************************\
  *                                                                           *
  * Driver init/exit                                                          *
@@ -556,6 +593,10 @@  static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
 
 	if (!host->mmc_host_ops.uhs2_detect_init)
 		host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
+	if (!host->mmc_host_ops.uhs2_disable_clk)
+		host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
+	if (!host->mmc_host_ops.uhs2_enable_clk)
+		host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
 
 	return 0;
 }