[RFC PATCH v1 09/19] rtw88: hci: Add an optional power_switch() callback to rtw_hci_ops

[Martin Blumenstingl]

32-bit SDIO bus reads/writes only work when the card is powered on. Add
an optional power_switch() callback to struct rtw_hci_ops where we
inform the HCI sub-driver that the chip is now powered on. Based on this
information the upcoming SDIO HCI implementation can then use the
appropriate 32-bit read/write accessors.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
---
 drivers/net/wireless/realtek/rtw88/hci.h | 8 ++++++++
 drivers/net/wireless/realtek/rtw88/mac.c | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/hci.h b/drivers/net/wireless/realtek/rtw88/hci.h
index 830d7532f2a3..602a6acc1ca1 100644
--- a/drivers/net/wireless/realtek/rtw88/hci.h
+++ b/drivers/net/wireless/realtek/rtw88/hci.h
@@ -22,6 +22,8 @@ struct rtw_hci_ops {
 	int (*write_data_rsvd_page)(struct rtw_dev *rtwdev, u8 *buf, u32 size);
 	int (*write_data_h2c)(struct rtw_dev *rtwdev, u8 *buf, u32 size);
 
+	void (*power_switch)(struct rtw_dev *rtwdev, bool on);
+
 	u8 (*read8)(struct rtw_dev *rtwdev, u32 addr);
 	u16 (*read16)(struct rtw_dev *rtwdev, u32 addr);
 	u32 (*read32)(struct rtw_dev *rtwdev, u32 addr);
@@ -84,6 +86,12 @@ rtw_hci_write_data_h2c(struct rtw_dev *rtwdev, u8 *buf, u32 size)
 	return rtwdev->hci.ops->write_data_h2c(rtwdev, buf, size);
 }
 
+static inline void rtw_hci_power_switch(struct rtw_dev *rtwdev, bool on)
+{
+	if (rtwdev->hci.ops->power_switch)
+		rtwdev->hci.ops->power_switch(rtwdev, on);
+}
+
 static inline u8 rtw_read8(struct rtw_dev *rtwdev, u32 addr)
 {
 	return rtwdev->hci.ops->read8(rtwdev, addr);
diff --git a/drivers/net/wireless/realtek/rtw88/mac.c b/drivers/net/wireless/realtek/rtw88/mac.c
index 4e5c194aac29..bf1291902661 100644
--- a/drivers/net/wireless/realtek/rtw88/mac.c
+++ b/drivers/net/wireless/realtek/rtw88/mac.c
@@ -269,10 +269,18 @@ static int rtw_mac_power_switch(struct rtw_dev *rtwdev, bool pwr_on)
 	if (pwr_on == cur_pwr)
 		return -EALREADY;
 
+	/* Always signal power off before power sequence. This way
+	 * read/write functions will take path which works in both
+	 * states. State will change in the middle of the sequence.
+	 */
+	rtw_hci_power_switch(rtwdev, false);
+
 	pwr_seq = pwr_on ? chip->pwr_on_seq : chip->pwr_off_seq;
 	if (rtw_pwr_seq_parser(rtwdev, pwr_seq))
 		return -EINVAL;
 
+	rtw_hci_power_switch(rtwdev, pwr_on);
+
 	return 0;
 }
 
-- 
2.39.0