wl1271: Implementation for SPI busy word checking

This patch adds implementation for checking for SPI busy words - i.e.
honoring a delay request from the WLAN chipset upon reading
registers/memory.

To optimized the average SPI ready by 32 bits, also configure the number
of busywords to one to disable the "fixed-busy-word" functionality.

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Reviewed-by: Vidhya Govindan <vidhya.govindan@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/net/wireless/wl12xx/wl1271.h b/drivers/net/wireless/wl12xx/wl1271.h
index c455dcbae524..957da8c0d9cb 100644
--- a/drivers/net/wireless/wl12xx/wl1271.h
+++ b/drivers/net/wireless/wl12xx/wl1271.h
@@ -107,7 +107,13 @@ enum {
 #define WL1271_FW_NAME "wl1271-fw.bin"
 #define WL1271_NVS_NAME "wl1271-nvs.bin"
 
-#define WL1271_BUSY_WORD_LEN 8
+/*
+ * FIXME: for the wl1271, a busy word count of 1 here will result in a more
+ * optimal SPI interface. There is some SPI bug however, causing RXS time outs
+ * with this mode occasionally on boot, so lets have two for now.
+ */
+#define WL1271_BUSY_WORD_CNT 2
+#define WL1271_BUSY_WORD_LEN (WL1271_BUSY_WORD_CNT * sizeof(u32))
 
 #define WL1271_ELP_HW_STATE_ASLEEP 0
 #define WL1271_ELP_HW_STATE_IRQ    1
@@ -389,7 +395,7 @@ struct wl1271 {
 
         u32 buffer_32;
         u32 buffer_cmd;
-        u8 buffer_busyword[WL1271_BUSY_WORD_LEN];
+        u32 buffer_busyword[WL1271_BUSY_WORD_CNT];
         struct wl1271_rx_descriptor *rx_descriptor;
 
         struct wl1271_fw_status *fw_status;