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SubjectRe: [PATCH v2 2/2] sdhci-of-arasan: Set controller to test mode when Card Detection is broken.
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On 2016/8/26 16:42, Mike Looijmans wrote:
> On 26-08-16 01:01, Zach Brown wrote:
>> The sdhci controller on xilinx zynq devices will not function unless
>> the CD bit is provided. http://www.xilinx.com/support/answers/61064.html
>> In cases where it is impossible to provide the CD bit in hardware,
>> setting the controller to test mode and then setting inserted to true
>> will get the controller to function without the CD bit.
>>
>> When the device has the property broken-cd the driver changes the
>> controller to test mode and sets test inserted to true to make the
>> controller function.
>>
>> Signed-off-by: Zach Brown <zach.brown@ni.com>
>> ---
>> drivers/mmc/host/sdhci-of-arasan.c | 17 ++++++++++++++++-
>> drivers/mmc/host/sdhci.h | 2 ++
>> 2 files changed, 18 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/sdhci-of-arasan.c
>> b/drivers/mmc/host/sdhci-of-arasan.c
>> index e0f193f..3798a3b 100644
>> --- a/drivers/mmc/host/sdhci-of-arasan.c
>> +++ b/drivers/mmc/host/sdhci-of-arasan.c
>> @@ -26,6 +26,7 @@
>> #include <linux/phy/phy.h>
>> #include <linux/regmap.h>
>> #include "sdhci-pltfm.h"
>> +#include <linux/of.h>
>
> Not needed.
>
>> #define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
>> #define SDHCI_ARASAN_VENDOR_REGISTER 0x78
>> @@ -203,12 +204,26 @@ static void
>> sdhci_arasan_hs400_enhanced_strobe(struct mmc_host *mmc,
>> writel(vendor, host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
>> }
>>
>> +void sdhci_arasan_reset(struct sdhci_host *host, u8 mask)
>> +{
>> + u8 ctrl;
>> +
>> + sdhci_reset(host, mask);
>> +
>> + if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) {
>> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
>> + ctrl |= SDHCI_CTRL_CDTEST_INS |
>> + SDHCI_CTRL_CDTEST_EN;
>> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
>> + }
>> +}

Although I don't have a "broken-cd" arasan controller,
but are you suring that all the broken-cd arasan controller
need to set these bit either? It seems your case is vendor specific?:)

>> +
>> static struct sdhci_ops sdhci_arasan_ops = {
>> .set_clock = sdhci_arasan_set_clock,
>> .get_max_clock = sdhci_pltfm_clk_get_max_clock,
>> .get_timeout_clock = sdhci_arasan_get_timeout_clock,
>> .set_bus_width = sdhci_set_bus_width,
>> - .reset = sdhci_reset,
>> + .reset = sdhci_arasan_reset,
>> .set_uhs_signaling = sdhci_set_uhs_signaling,
>> };
>>
>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>> index 0411c9f..8d92d6e9 100644
>> --- a/drivers/mmc/host/sdhci.h
>> +++ b/drivers/mmc/host/sdhci.h
>> @@ -84,6 +84,8 @@
>> #define SDHCI_CTRL_ADMA32 0x10
>> #define SDHCI_CTRL_ADMA64 0x18
>> #define SDHCI_CTRL_8BITBUS 0x20
>> +#define SDHCI_CTRL_CDTEST_INS 0x40
>> +#define SDHCI_CTRL_CDTEST_EN 0x80
>>
>> #define SDHCI_POWER_CONTROL 0x29
>> #define SDHCI_POWER_ON 0x01
>
> Looks okay, tested it and appears to work just as well as a tie-off in
> logic.
>
> Tested-by: mike.looijmans@topic.nl
>
>
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>


--
Best Regards
Shawn Lin

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