From: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx> [ Upstream commit ed04ea76e69e7194f7489cebe23a32a68f39218d ] When deiniting the DXE hardware we should reset the block to ensure there is no spurious DMA write transaction from the downstream WCNSS to upstream MSM at a skbuff address we will have released. Fixes: 8e84c2582169 ("wcn36xx: mac80211 driver for Qualcomm WCN3660/WCN3680 hardware") Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20211105122152.1580542-4-bryan.odonoghue@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/wireless/ath/wcn36xx/dxe.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/wireless/ath/wcn36xx/dxe.c b/drivers/net/wireless/ath/wcn36xx/dxe.c index 017c7d78072ba..e1a35c2eadb6c 100644 --- a/drivers/net/wireless/ath/wcn36xx/dxe.c +++ b/drivers/net/wireless/ath/wcn36xx/dxe.c @@ -997,6 +997,8 @@ out_err_txh_ch: void wcn36xx_dxe_deinit(struct wcn36xx *wcn) { + int reg_data = 0; + /* Disable channel interrupts */ wcn36xx_dxe_disable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H); wcn36xx_dxe_disable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L); @@ -1012,6 +1014,10 @@ void wcn36xx_dxe_deinit(struct wcn36xx *wcn) wcn->tx_ack_skb = NULL; } + /* Put the DXE block into reset before freeing memory */ + reg_data = WCN36XX_DXE_REG_RESET; + wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data); + wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch); wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch); -- 2.34.1