Return-path: Received: from s131.mittwaldmedien.de ([62.216.178.31]:15067 "EHLO s131.mittwaldmedien.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753436AbYEZKub (ORCPT ); Mon, 26 May 2008 06:50:31 -0400 From: Holger Schurig To: libertas-dev@lists.infradead.org, Dan Williams , linux-wireless@vger.kernel.org, "John W. Linville" Subject: [PATCH, take 3] libertas: fix compact flash interrupt handling Date: Mon, 26 May 2008 12:50:23 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Message-Id: <200805261250.23580.hs4233@mail.mn-solutions.de> (sfid-20080526_125034_983233_3C94F7A7) Sender: linux-wireless-owner@vger.kernel.org List-ID: The old code misbehaved because it polled card status and always called the "tx over" code-path. This also fixes a hard lockup by not allowing and card interrupts while transferring a TX frame or a command into the card. Signed-off-by: Holger Schurig Index: wireless-testing/drivers/net/wireless/libertas/if_cs.c =================================================================== --- wireless-testing.orig/drivers/net/wireless/libertas/if_cs.c 2008-05-26 08:53:27.000000000 +0200 +++ wireless-testing/drivers/net/wireless/libertas/if_cs.c 2008-05-26 10:27:24.000000000 +0200 @@ -215,9 +215,21 @@ static int if_cs_poll_while_fw_download( /********************************************************************/ -/* I/O */ +/* I/O and interrupt handling */ /********************************************************************/ +static inline void if_cs_enable_ints(struct if_cs_card *card) +{ + lbs_deb_enter(LBS_DEB_CS); + if_cs_write16(card, IF_CS_H_INT_MASK, 0); +} + +static inline void if_cs_disable_ints(struct if_cs_card *card) +{ + lbs_deb_enter(LBS_DEB_CS); + if_cs_write16(card, IF_CS_H_INT_MASK, IF_CS_H_IM_MASK); +} + /* * Called from if_cs_host_to_card to send a command to the hardware */ @@ -228,6 +240,7 @@ static int if_cs_send_cmd(struct lbs_pri int loops = 0; lbs_deb_enter(LBS_DEB_CS); + if_cs_disable_ints(card); /* Is hardware ready? */ while (1) { @@ -258,19 +271,24 @@ static int if_cs_send_cmd(struct lbs_pri ret = 0; done: + if_cs_enable_ints(card); lbs_deb_leave_args(LBS_DEB_CS, "ret %d", ret); return ret; } - /* * Called from if_cs_host_to_card to send a data to the hardware */ static void if_cs_send_data(struct lbs_private *priv, u8 *buf, u16 nb) { struct if_cs_card *card = (struct if_cs_card *)priv->card; + u16 status; lbs_deb_enter(LBS_DEB_CS); + if_cs_disable_ints(card); + + status = if_cs_read16(card, IF_CS_C_STATUS); + BUG_ON((status & IF_CS_C_S_TX_DNLD_RDY) == 0); if_cs_write16(card, IF_CS_H_WRITE_LEN, nb); @@ -281,11 +299,11 @@ static void if_cs_send_data(struct lbs_p if_cs_write16(card, IF_CS_H_STATUS, IF_CS_H_STATUS_TX_OVER); if_cs_write16(card, IF_CS_H_INT_CAUSE, IF_CS_H_STATUS_TX_OVER); + if_cs_enable_ints(card); lbs_deb_leave(LBS_DEB_CS); } - /* * Get the command result out of the card. */ @@ -330,7 +348,6 @@ out: return ret; } - static struct sk_buff *if_cs_receive_data(struct lbs_private *priv) { struct sk_buff *skb = NULL; @@ -367,25 +384,6 @@ out: return skb; } - - -/********************************************************************/ -/* Interrupts */ -/********************************************************************/ - -static inline void if_cs_enable_ints(struct if_cs_card *card) -{ - lbs_deb_enter(LBS_DEB_CS); - if_cs_write16(card, IF_CS_H_INT_MASK, 0); -} - -static inline void if_cs_disable_ints(struct if_cs_card *card) -{ - lbs_deb_enter(LBS_DEB_CS); - if_cs_write16(card, IF_CS_H_INT_MASK, IF_CS_H_IM_MASK); -} - - static irqreturn_t if_cs_interrupt(int irq, void *data) { struct if_cs_card *card = data; @@ -394,10 +392,8 @@ static irqreturn_t if_cs_interrupt(int i lbs_deb_enter(LBS_DEB_CS); + /* Ask card interrupt cause register if there is something for us */ cause = if_cs_read16(card, IF_CS_C_INT_CAUSE); - if_cs_write16(card, IF_CS_C_INT_CAUSE, cause & IF_CS_C_IC_MASK); - - lbs_deb_cs("cause 0x%04x\n", cause); if (cause == 0) { /* Not for us */ return IRQ_NONE; @@ -409,9 +405,9 @@ static irqreturn_t if_cs_interrupt(int i return IRQ_HANDLED; } - /* TODO: I'm not sure what the best ordering is */ - - cause = if_cs_read16(card, IF_CS_C_STATUS) & IF_CS_C_S_MASK; + /* Clear interrupt cause */ + if_cs_write16(card, IF_CS_C_INT_CAUSE, cause & IF_CS_C_IC_MASK); + lbs_deb_cs("cause 0x%04x\n", cause); if (cause & IF_CS_C_S_RX_UPLD_RDY) { struct sk_buff *skb; @@ -422,7 +418,7 @@ static irqreturn_t if_cs_interrupt(int i } if (cause & IF_CS_H_IC_TX_OVER) { - lbs_deb_cs("tx over\n"); + lbs_deb_cs("tx done\n"); lbs_host_to_card_done(priv); } @@ -430,7 +426,7 @@ static irqreturn_t if_cs_interrupt(int i unsigned long flags; u8 i; - lbs_deb_cs("cmd upload ready\n"); + lbs_deb_cs("cmd resp\n"); spin_lock_irqsave(&priv->driver_lock, flags); i = (priv->resp_idx == 0) ? 1 : 0; spin_unlock_irqrestore(&priv->driver_lock, flags); @@ -449,10 +445,11 @@ static irqreturn_t if_cs_interrupt(int i & IF_CS_C_S_STATUS_MASK; if_cs_write16(priv->card, IF_CS_H_INT_CAUSE, IF_CS_H_IC_HOST_EVENT); - lbs_deb_cs("eventcause 0x%04x\n", event); + lbs_deb_cs("host event 0x%04x\n", event); lbs_queue_event(priv, event >> 8 & 0xff); } + lbs_deb_leave(LBS_DEB_CS); return IRQ_HANDLED; }