| Message ID | 1448237747-20037-2-git-send-email-steve.derosier@lairdtech.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Kalle Valo |
| Headers | show |
Steve deRosier <derosier@gmail.com> writes: > Many ath6k chips have a reset pin, usually labeled CHIP_PWD_L. This pin can > be pulled low by the host processor to hold the wifi chip in reset. By > holding the chip in reset, the lowest power consumption available can be > achieved. > > This adds a module parameter so the ath6kl_sdio driver can control the > CHIP_PWD_L pin if the implementer so desires. This code is only available > if GPIOLIB is configured. > > Signed-off-by: Steve deRosier <steve.derosier@lairdtech.com> I haven't reviewed the patch yet but at least it doesn't compile on 32bit x86: CC [M] drivers/net/wireless/ath/ath6kl/sdio.o drivers/net/wireless/ath/ath6kl/sdio.c:81:38: error: ‘ARCH_NR_GPIOS’ undeclared here (not in a function)
Hi Steve,
[auto build test ERROR on net-next/master]
[also build test ERROR on v4.4-rc3 next-20151203]
url: https://github.com/0day-ci/linux/commits/Steve-deRosier/ath6kl_sdio-add-control-of-CHIP_PWD_L-via-GPIO/20151123-123006
config: mips-allmodconfig (attached as .config)
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=mips
All errors (new ones prefixed by >>):
>> drivers/net/wireless/ath/ath6kl/sdio.c:81:38: error: 'ARCH_NR_GPIOS' undeclared here (not in a function)
static unsigned int reset_pwd_gpio = ARCH_NR_GPIOS;
^
vim +/ARCH_NR_GPIOS +81 drivers/net/wireless/ath/ath6kl/sdio.c
75 * spurious warning:
76 * "ath6kl_sdio: probe of mmc0:0001:1 failed with error -110"
77 *
78 * Time chosen experimentally, with padding
79 */
80 #define ATH6KL_MMC_PROBE_DELAY 150
> 81 static unsigned int reset_pwd_gpio = ARCH_NR_GPIOS;
82 #ifdef CONFIG_GPIOLIB
83 module_param(reset_pwd_gpio, uint, 0644);
84 MODULE_PARM_DESC(reset_pwd_gpio, "WIFI CHIP_PWD reset pin GPIO");
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/drivers/net/wireless/ath/ath6kl/sdio.c b/drivers/net/wireless/ath/ath6kl/sdio.c index eab0ab9..d06aa41 100644 --- a/drivers/net/wireless/ath/ath6kl/sdio.c +++ b/drivers/net/wireless/ath/ath6kl/sdio.c @@ -23,6 +23,7 @@ #include <linux/mmc/sdio_ids.h> #include <linux/mmc/sdio.h> #include <linux/mmc/sd.h> +#include <linux/gpio.h> #include "hif.h" #include "hif-ops.h" #include "target.h" @@ -69,6 +70,20 @@ struct ath6kl_sdio { spinlock_t wr_async_lock; }; +/* Delay to avoid the mmc driver calling the probe on the prior notice of + * the chip, which we just killed. If this is missing, it results in a + * spurious warning: + * "ath6kl_sdio: probe of mmc0:0001:1 failed with error -110" + * + * Time chosen experimentally, with padding + */ +#define ATH6KL_MMC_PROBE_DELAY 150 +static unsigned int reset_pwd_gpio = ARCH_NR_GPIOS; +#ifdef CONFIG_GPIOLIB +module_param(reset_pwd_gpio, uint, 0644); +MODULE_PARM_DESC(reset_pwd_gpio, "WIFI CHIP_PWD reset pin GPIO"); +#endif + #define CMD53_ARG_READ 0 #define CMD53_ARG_WRITE 1 #define CMD53_ARG_BLOCK_BASIS 1 @@ -1414,20 +1429,73 @@ static struct sdio_driver ath6kl_sdio_driver = { .drv.pm = ATH6KL_SDIO_PM_OPS, }; +static int ath6kl_sdio_init_gpio(void) +{ + int ret = 0; + + if (gpio_is_valid(reset_pwd_gpio)) { + /* Request the reset GPIO, and assert it to make sure we get a + * clean boot in-case we had a floating input or other issue. + */ + ret = gpio_request_one(reset_pwd_gpio, + GPIOF_OUT_INIT_LOW | + GPIOF_EXPORT_DIR_FIXED, + "WIFI_RESET"); + if (ret) { + ath6kl_err("Unable to get WIFI power gpio: %d\n", ret); + return ret; + } + + ath6kl_dbg(ATH6KL_DBG_SUSPEND, "Setup wifi gpio #%d\n", + reset_pwd_gpio); + usleep_range(20, 50); /* Pin must be asserted at least 5 usec */ + gpio_set_value(reset_pwd_gpio, 1); /* De-assert the pin */ + + msleep(ATH6KL_MMC_PROBE_DELAY); + } + + return 0; +} + +static void ath6kl_sdio_release_gpio(void) +{ + if (gpio_is_valid(reset_pwd_gpio)) { + /* Be sure we leave the chip in reset when we unload and also + * release the GPIO + */ + gpio_set_value(reset_pwd_gpio, 0); + gpio_free(reset_pwd_gpio); + } +} + static int __init ath6kl_sdio_init(void) { int ret; - ret = sdio_register_driver(&ath6kl_sdio_driver); + ret = ath6kl_sdio_init_gpio(); if (ret) + goto err_gpio; + + ret = sdio_register_driver(&ath6kl_sdio_driver); + if (ret) { ath6kl_err("sdio driver registration failed: %d\n", ret); + goto err_register; + } return ret; + +err_register: + ath6kl_sdio_release_gpio(); + +err_gpio: + return ret; } static void __exit ath6kl_sdio_exit(void) { sdio_unregister_driver(&ath6kl_sdio_driver); + + ath6kl_sdio_release_gpio(); } module_init(ath6kl_sdio_init);
Many ath6k chips have a reset pin, usually labeled CHIP_PWD_L. This pin can be pulled low by the host processor to hold the wifi chip in reset. By holding the chip in reset, the lowest power consumption available can be achieved. This adds a module parameter so the ath6kl_sdio driver can control the CHIP_PWD_L pin if the implementer so desires. This code is only available if GPIOLIB is configured. Signed-off-by: Steve deRosier <steve.derosier@lairdtech.com> --- drivers/net/wireless/ath/ath6kl/sdio.c | 70 +++++++++++++++++++++++++++++++++- 1 file changed, 69 insertions(+), 1 deletion(-)