Re: [PATCH] HID: intel-ish-hid: fix module device-id handling

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 11/11/21 09:56, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> A late addititon to the intel-ish-hid framework caused a build failure
> with clang, and introduced an ABI to the module loader that stops working
> if any driver ever needs to bind to more than one UUID:
> 
> drivers/hid/intel-ish-hid/ishtp-fw-loader.c:1067:4: error: initializer element is not a compile-time constant
> 
> Change the ishtp_device_id to have correct documentation and a driver_data
> field like all the other ones, and change the drivers to use the ID table
> as the primary identification in a way that works with all compilers
> and avoids duplciating the identifiers.
> 
> Fixes: f155dfeaa4ee ("platform/x86: isthp_eclite: only load for matching devices")
> Fixes: facfe0a4fdce ("platform/chrome: chros_ec_ishtp: only load for matching devices")
> Fixes: 0d0cccc0fd83 ("HID: intel-ish-hid: hid-client: only load for matching devices")
> Fixes: 44e2a58cb880 ("HID: intel-ish-hid: fw-loader: only load for matching devices")
> Fixes: cb1a2c6847f7 ("HID: intel-ish-hid: use constants for modaliases")
> Fixes: fa443bc3c1e4 ("HID: intel-ish-hid: add support for MODULE_DEVICE_TABLE()")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> I did not see this reported on the list so far, but it has probably
> shown up in other build bots as well.
> 
> There are lots of ways to fix the warning, I picked this way to address
> the more urgent problem of fixing the mod_devicetable.h format before
> it is too late for that.

Thank you for fixing this, patch looks good to me:

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans




> ---
>  drivers/hid/intel-ish-hid/ishtp-fw-loader.c  | 19 ++++++++-----------
>  drivers/hid/intel-ish-hid/ishtp-hid-client.c | 19 ++++++++-----------
>  drivers/hid/intel-ish-hid/ishtp/bus.c        |  2 +-
>  drivers/platform/chrome/cros_ec_ishtp.c      | 19 ++++++++-----------
>  drivers/platform/x86/intel/ishtp_eclite.c    | 19 ++++++++-----------
>  include/linux/intel-ish-client-if.h          |  4 ++--
>  include/linux/mod_devicetable.h              |  5 +++--
>  7 files changed, 38 insertions(+), 49 deletions(-)
> 
> diff --git a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> index 945a9d0b68cd..0e1183e96147 100644
> --- a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> +++ b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> @@ -76,9 +76,12 @@ enum ish_loader_commands {
>  #define LOADER_XFER_MODE_ISHTP			BIT(1)
>  
>  /* ISH Transport Loader client unique GUID */
> -static const guid_t loader_ishtp_guid =
> -	GUID_INIT(0xc804d06a, 0x55bd, 0x4ea7,
> -		  0xad, 0xed, 0x1e, 0x31, 0x22, 0x8c, 0x76, 0xdc);
> +static const struct ishtp_device_id loader_ishtp_id_table[] = {
> +	{ .guid = GUID_INIT(0xc804d06a, 0x55bd, 0x4ea7,
> +		  0xad, 0xed, 0x1e, 0x31, 0x22, 0x8c, 0x76, 0xdc) },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(ishtp, loader_ishtp_id_table);
>  
>  #define FILENAME_SIZE				256
>  
> @@ -880,7 +883,7 @@ static int loader_init(struct ishtp_cl *loader_ishtp_cl, int reset)
>  
>  	fw_client =
>  		ishtp_fw_cl_get_client(ishtp_get_ishtp_device(loader_ishtp_cl),
> -				       &loader_ishtp_guid);
> +				       &loader_ishtp_id_table[0].guid);
>  	if (!fw_client) {
>  		dev_err(cl_data_to_dev(client_data),
>  			"ISH client uuid not found\n");
> @@ -1057,18 +1060,12 @@ static int loader_ishtp_cl_reset(struct ishtp_cl_device *cl_device)
>  
>  static struct ishtp_cl_driver	loader_ishtp_cl_driver = {
>  	.name = "ish-loader",
> -	.guid = &loader_ishtp_guid,
> +	.id = loader_ishtp_id_table,
>  	.probe = loader_ishtp_cl_probe,
>  	.remove = loader_ishtp_cl_remove,
>  	.reset = loader_ishtp_cl_reset,
>  };
>  
> -static const struct ishtp_device_id loader_ishtp_id_table[] = {
> -	{ loader_ishtp_guid },
> -	{ }
> -};
> -MODULE_DEVICE_TABLE(ishtp, loader_ishtp_id_table);
> -
>  static int __init ish_loader_init(void)
>  {
>  	return ishtp_cl_driver_register(&loader_ishtp_cl_driver, THIS_MODULE);
> diff --git a/drivers/hid/intel-ish-hid/ishtp-hid-client.c b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> index fb47d38d1e87..4338c9b68a43 100644
> --- a/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> +++ b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> @@ -12,9 +12,12 @@
>  #include "ishtp-hid.h"
>  
>  /* ISH Transport protocol (ISHTP in short) GUID */
> -static const guid_t hid_ishtp_guid =
> -	GUID_INIT(0x33AECD58, 0xB679, 0x4E54,
> -		  0x9B, 0xD9, 0xA0, 0x4D, 0x34, 0xF0, 0xC2, 0x26);
> +static const struct ishtp_device_id hid_ishtp_id_table[] = {
> +	{ .guid = GUID_INIT(0x33AECD58, 0xB679, 0x4E54,
> +		  0x9B, 0xD9, 0xA0, 0x4D, 0x34, 0xF0, 0xC2, 0x26), },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(ishtp, hid_ishtp_id_table);
>  
>  /* Rx ring buffer pool size */
>  #define HID_CL_RX_RING_SIZE	32
> @@ -662,7 +665,7 @@ static int hid_ishtp_cl_init(struct ishtp_cl *hid_ishtp_cl, int reset)
>  	ishtp_set_tx_ring_size(hid_ishtp_cl, HID_CL_TX_RING_SIZE);
>  	ishtp_set_rx_ring_size(hid_ishtp_cl, HID_CL_RX_RING_SIZE);
>  
> -	fw_client = ishtp_fw_cl_get_client(dev, &hid_ishtp_guid);
> +	fw_client = ishtp_fw_cl_get_client(dev, &hid_ishtp_id_table[0].guid);
>  	if (!fw_client) {
>  		dev_err(cl_data_to_dev(client_data),
>  			"ish client uuid not found\n");
> @@ -945,19 +948,13 @@ static const struct dev_pm_ops hid_ishtp_pm_ops = {
>  
>  static struct ishtp_cl_driver	hid_ishtp_cl_driver = {
>  	.name = "ish-hid",
> -	.guid = &hid_ishtp_guid,
> +	.id = hid_ishtp_id_table,
>  	.probe = hid_ishtp_cl_probe,
>  	.remove = hid_ishtp_cl_remove,
>  	.reset = hid_ishtp_cl_reset,
>  	.driver.pm = &hid_ishtp_pm_ops,
>  };
>  
> -static const struct ishtp_device_id hid_ishtp_id_table[] = {
> -	{ hid_ishtp_guid },
> -	{ }
> -};
> -MODULE_DEVICE_TABLE(ishtp, hid_ishtp_id_table);
> -
>  static int __init ish_hid_init(void)
>  {
>  	int	rv;
> diff --git a/drivers/hid/intel-ish-hid/ishtp/bus.c b/drivers/hid/intel-ish-hid/ishtp/bus.c
> index e159cd1c5f37..f68aba8794fe 100644
> --- a/drivers/hid/intel-ish-hid/ishtp/bus.c
> +++ b/drivers/hid/intel-ish-hid/ishtp/bus.c
> @@ -241,7 +241,7 @@ static int ishtp_cl_bus_match(struct device *dev, struct device_driver *drv)
>  	struct ishtp_cl_device *device = to_ishtp_cl_device(dev);
>  	struct ishtp_cl_driver *driver = to_ishtp_cl_driver(drv);
>  
> -	return guid_equal(driver->guid,
> +	return guid_equal(&driver->id[0].guid,
>  			  &device->fw_client->props.protocol_name);
>  }
>  
> diff --git a/drivers/platform/chrome/cros_ec_ishtp.c b/drivers/platform/chrome/cros_ec_ishtp.c
> index 8c17358e84c1..4020b8354bae 100644
> --- a/drivers/platform/chrome/cros_ec_ishtp.c
> +++ b/drivers/platform/chrome/cros_ec_ishtp.c
> @@ -41,9 +41,12 @@ enum cros_ec_ish_channel {
>  #define ISHTP_SEND_TIMEOUT			(3 * HZ)
>  
>  /* ISH Transport CrOS EC ISH client unique GUID */
> -static const guid_t cros_ish_guid =
> -	GUID_INIT(0x7b7154d0, 0x56f4, 0x4bdc,
> -		  0xb0, 0xd8, 0x9e, 0x7c, 0xda,	0xe0, 0xd6, 0xa0);
> +static const struct ishtp_device_id cros_ec_ishtp_id_table[] = {
> +	{ .guid = GUID_INIT(0x7b7154d0, 0x56f4, 0x4bdc,
> +		  0xb0, 0xd8, 0x9e, 0x7c, 0xda,	0xe0, 0xd6, 0xa0), },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(ishtp, cros_ec_ishtp_id_table);
>  
>  struct header {
>  	u8 channel;
> @@ -389,7 +392,7 @@ static int cros_ish_init(struct ishtp_cl *cros_ish_cl)
>  	ishtp_set_tx_ring_size(cros_ish_cl, CROS_ISH_CL_TX_RING_SIZE);
>  	ishtp_set_rx_ring_size(cros_ish_cl, CROS_ISH_CL_RX_RING_SIZE);
>  
> -	fw_client = ishtp_fw_cl_get_client(dev, &cros_ish_guid);
> +	fw_client = ishtp_fw_cl_get_client(dev, &cros_ec_ishtp_id_table[0].guid);
>  	if (!fw_client) {
>  		dev_err(cl_data_to_dev(client_data),
>  			"ish client uuid not found\n");
> @@ -765,7 +768,7 @@ static SIMPLE_DEV_PM_OPS(cros_ec_ishtp_pm_ops, cros_ec_ishtp_suspend,
>  
>  static struct ishtp_cl_driver	cros_ec_ishtp_driver = {
>  	.name = "cros_ec_ishtp",
> -	.guid = &cros_ish_guid,
> +	.id = cros_ec_ishtp_id_table,
>  	.probe = cros_ec_ishtp_probe,
>  	.remove = cros_ec_ishtp_remove,
>  	.reset = cros_ec_ishtp_reset,
> @@ -774,12 +777,6 @@ static struct ishtp_cl_driver	cros_ec_ishtp_driver = {
>  	},
>  };
>  
> -static const struct ishtp_device_id cros_ec_ishtp_id_table[] = {
> -	{ cros_ish_guid },
> -	{ }
> -};
> -MODULE_DEVICE_TABLE(ishtp, cros_ec_ishtp_id_table);
> -
>  static int __init cros_ec_ishtp_mod_init(void)
>  {
>  	return ishtp_cl_driver_register(&cros_ec_ishtp_driver, THIS_MODULE);
> diff --git a/drivers/platform/x86/intel/ishtp_eclite.c b/drivers/platform/x86/intel/ishtp_eclite.c
> index b9fb8f28fd63..b2da3a4b3e1b 100644
> --- a/drivers/platform/x86/intel/ishtp_eclite.c
> +++ b/drivers/platform/x86/intel/ishtp_eclite.c
> @@ -93,9 +93,12 @@ struct ishtp_opregion_dev {
>  };
>  
>  /* eclite ishtp client UUID: 6a19cc4b-d760-4de3-b14d-f25ebd0fbcd9 */
> -static const guid_t ecl_ishtp_guid =
> -	GUID_INIT(0x6a19cc4b, 0xd760, 0x4de3,
> -		  0xb1, 0x4d, 0xf2, 0x5e, 0xbd, 0xf, 0xbc, 0xd9);
> +static const struct ishtp_device_id ecl_ishtp_id_table[] = {
> +	{ .guid = GUID_INIT(0x6a19cc4b, 0xd760, 0x4de3,
> +		  0xb1, 0x4d, 0xf2, 0x5e, 0xbd, 0xf, 0xbc, 0xd9), },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(ishtp, ecl_ishtp_id_table);
>  
>  /* ACPI DSM UUID: 91d936a7-1f01-49c6-a6b4-72f00ad8d8a5 */
>  static const guid_t ecl_acpi_guid =
> @@ -462,7 +465,7 @@ static int ecl_ishtp_cl_init(struct ishtp_cl *ecl_ishtp_cl)
>  	ishtp_set_tx_ring_size(ecl_ishtp_cl, ECL_CL_TX_RING_SIZE);
>  	ishtp_set_rx_ring_size(ecl_ishtp_cl, ECL_CL_RX_RING_SIZE);
>  
> -	fw_client = ishtp_fw_cl_get_client(dev, &ecl_ishtp_guid);
> +	fw_client = ishtp_fw_cl_get_client(dev, &ecl_ishtp_id_table[0].guid);
>  	if (!fw_client) {
>  		dev_err(cl_data_to_dev(opr_dev), "fw client not found\n");
>  		return -ENOENT;
> @@ -674,19 +677,13 @@ static const struct dev_pm_ops ecl_ishtp_pm_ops = {
>  
>  static struct ishtp_cl_driver ecl_ishtp_cl_driver = {
>  	.name = "ishtp-eclite",
> -	.guid = &ecl_ishtp_guid,
> +	.id = &ecl_ishtp_id_table,
>  	.probe = ecl_ishtp_cl_probe,
>  	.remove = ecl_ishtp_cl_remove,
>  	.reset = ecl_ishtp_cl_reset,
>  	.driver.pm = &ecl_ishtp_pm_ops,
>  };
>  
> -static const struct ishtp_device_id ecl_ishtp_id_table[] = {
> -	{ ecl_ishtp_guid },
> -	{ }
> -};
> -MODULE_DEVICE_TABLE(ishtp, ecl_ishtp_id_table);
> -
>  static int __init ecl_ishtp_init(void)
>  {
>  	return ishtp_cl_driver_register(&ecl_ishtp_cl_driver, THIS_MODULE);
> diff --git a/include/linux/intel-ish-client-if.h b/include/linux/intel-ish-client-if.h
> index aee8ff4739b1..f45f13304add 100644
> --- a/include/linux/intel-ish-client-if.h
> +++ b/include/linux/intel-ish-client-if.h
> @@ -9,7 +9,7 @@
>  #define _INTEL_ISH_CLIENT_IF_H_
>  
>  #include <linux/device.h>
> -#include <linux/uuid.h>
> +#include <linux/mod_devicetable.h>
>  
>  struct ishtp_cl_device;
>  struct ishtp_device;
> @@ -40,7 +40,7 @@ enum cl_state {
>  struct ishtp_cl_driver {
>  	struct device_driver driver;
>  	const char *name;
> -	const guid_t *guid;
> +	const struct ishtp_device_id *id;
>  	int (*probe)(struct ishtp_cl_device *dev);
>  	void (*remove)(struct ishtp_cl_device *dev);
>  	int (*reset)(struct ishtp_cl_device *dev);
> diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
> index befbf53c4b7c..bcfd5357c9a5 100644
> --- a/include/linux/mod_devicetable.h
> +++ b/include/linux/mod_devicetable.h
> @@ -901,11 +901,12 @@ struct dfl_device_id {
>  
>  /**
>   * struct ishtp_device_id - ISHTP device identifier
> - * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
> - * @context: pointer to driver specific data
> + * @guid: 16-byte binary guid representation
> + * @driver_data: pointer to driver specific data
>   */
>  struct ishtp_device_id {
>  	guid_t guid;
> +	kernel_ulong_t driver_data;
>  };
>  
>  #endif /* LINUX_MOD_DEVICETABLE_H */
>