iwlwifi: remove power-wasting calls to apm_ops.init()

To save power, don't run apm_ops.init() until needed at "up" time.

EEPROM (5000 and earlier devices) may be read without running apm_ops.init(),
but OTP reads (6000 and newer devices) require a powered-up chip.
Therefore, remove apm_ops.init() from the general path in XXXX_pci_probe(),
and call it only if device uses OTP.  Once done with OTP read, call
apm_ops.stop() to reset chip and save power until "up" time comes around.

NOTE:  This patch depends on removal of priv->lock from iwl_apm_stop();
lock does not get initialized until later in flow.  See patch
"remove unneeded locks from apm_stop()".

Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
index 9429cb1c69bd..8a0709e81a9f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
@@ -533,6 +533,10 @@ int iwl_eeprom_init(struct iwl_priv *priv)
                 goto err;
         }
         if (priv->nvm_device_type == NVM_DEVICE_TYPE_OTP) {
+
+                /* OTP reads require powered-up chip */
+                priv->cfg->ops->lib->apm_ops.init(priv);
+
                 ret = iwl_init_otp_access(priv);
                 if (ret) {
                         IWL_ERR(priv, "Failed to initialize OTP access.\n");
@@ -563,6 +567,13 @@ int iwl_eeprom_init(struct iwl_priv *priv)
                         e[cache_addr / 2] = eeprom_data;
                         cache_addr += sizeof(u16);
                 }
+
+                /*
+                 * Now that OTP reads are complete, reset chip to save
+                 *   power until we load uCode during "up".
+                 */
+                priv->cfg->ops->lib->apm_ops.stop(priv);
+
         } else {
                 /* eeprom is an array of 16bit values */
                 for (addr = 0; addr < sz; addr += sizeof(u16)) {