Re: [PATCH v3 resend 2/3] mmc: sdhci-acpi: Add blacklist module option

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

On 07-06-17 14:47, Adrian Hunter wrote:
On 24/05/17 13:47, Hans de Goede wrote:
Commit e5bbf30733f9 ("mmc: sdhci-acpi: Ensure connected devices are
powered when probing") introduced unconditional calling of
acpi_device_fix_up_power() on the mmc controller and its children.

This broke wifi on some systems because acpi_device_fix_up_power()
was called even for disabled children sometimes leaving gpio-s in
a state where wifi would not work, this was fixed in
commit e1d070c3793a ("mmc: sdhci-acpi: Only powered up enabled acpi
child devices").

Unfortunately on some devices calling acpi_device_fix_up_power()
still causes issues. Specifically on the GPD-win mini clam-shell PC
which has a pci-e wifi module, it causes the wifi module to get
turned off. This is a BIOS bug and I've tried to get the manufacturer
to fix this but sofar they have not responded (and even if they do
then we cannot assume all users will update their BIOS).

Since the GPD-win uses a pci-e wifi module the sdhci controller for
sdio cards really should not get initialized on it at all.

This commit adds a new sdhci_acpi.blacklist module option which can
be set to an ACPI hid:uid pair, e.g. "80860F14:2" to disable probing
for the sdhci host matching the hid:uid pair, fixing the wifi not
working on this machine.

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v2:
-Make the module option take a hid:uid pair string, instead of it
  being a boolean option, so that it only applies to one host
Changes in v3:
-Make the module option skip probing the device entirely (return -ENODEV)
---
  drivers/mmc/host/sdhci-acpi.c | 36 +++++++++++++++++++++++++++++++++---
  1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
index 89d9a8c014f5..3a7d979a306d 100644
--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -83,6 +83,29 @@ struct sdhci_acpi_host {
  	bool				use_runtime_pm;
  };
+static char *blacklist;
+
+static bool sdhci_acpi_compare_hid_uid(const char *match, const char *hid,
+				       const char *uid)
+{
+	const char *sep;
+
+	if (!match)
+		return false;
+
+	sep = strchr(match, ':');
+	if (!match)

You mean (!sep)

Right, will fix for v4.

+		return false;
+
+	if (strncmp(match, hid, sep - match))
+		return false;
+
+	if (strcmp(sep + 1, uid))
+		return false;
+
+	return true;

This should all go together i.e.
>
	return sep && !strncmp(match, hid, sep - match) &&
	       !strcmp(sep + 1, uid);

Ok.


+}
+
  static inline bool sdhci_acpi_flag(struct sdhci_acpi_host *c, unsigned int flag)
  {
  	return c->slot && (c->slot->flags & flag);
@@ -378,6 +401,7 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
  {
  	struct device *dev = &pdev->dev;
  	acpi_handle handle = ACPI_HANDLE(dev);
+	const char *bl = blacklist;
  	struct acpi_device *device, *child;
  	struct sdhci_acpi_host *c;
  	struct sdhci_host *host;
@@ -390,6 +414,12 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
  	if (acpi_bus_get_device(handle, &device))
  		return -ENODEV;
+ hid = acpi_device_hid(device);
+	uid = device->pnp.unique_id;
+
+	if (sdhci_acpi_compare_hid_uid(bl, hid, uid))

'bl' is redundant in this patch.  This should just be

	if (sdhci_acpi_blacklist(hid, uid))
		return -ENODEV;

+		return -ENODEV;
+
  	/* Power on the SDHCI controller and its children */
  	acpi_device_fix_up_power(device);
  	list_for_each_entry(child, &device->children, node)
@@ -399,9 +429,6 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
  	if (sdhci_acpi_byt_defer(dev))
  		return -EPROBE_DEFER;
- hid = acpi_device_hid(device);
-	uid = device->pnp.unique_id;
-
  	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!iomem)
  		return -ENOMEM;
@@ -580,6 +607,9 @@ static struct platform_driver sdhci_acpi_driver = {
module_platform_driver(sdhci_acpi_driver); +module_param(blacklist, charp, 0444);
+MODULE_PARM_DESC(blacklist, "ACPI <HID:UID> which should be ignored");

Why not allow more than one HID:UID separated by commas.

I didn't think we will ever have the need to blacklist more then
1 HID:UID pair and it makes the parsing slightly harder. But since you've
asked I'll add support for this for v4.

Regards,

Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux USB Devel]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux