Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933273AbaLKUGf (ORCPT ); Thu, 11 Dec 2014 15:06:35 -0500 Received: from mailapp01.imgtec.com ([195.59.15.196]:14528 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758732AbaLKUF6 (ORCPT ); Thu, 11 Dec 2014 15:05:58 -0500 From: Sifan Naeem To: , CC: , , , , Sifan Naeem Subject: [PATCH v2 3/5] rc: img-ir: biphase enabled with workaround Date: Thu, 11 Dec 2014 20:06:24 +0000 Message-ID: <1418328386-9802-4-git-send-email-sifan.naeem@imgtec.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1418328386-9802-1-git-send-email-sifan.naeem@imgtec.com> References: <1418328386-9802-1-git-send-email-sifan.naeem@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.167.63] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Biphase decoding in the current img-ir has got a quirk, where multiple Interrupts are generated when an incomplete IR code is received by the decoder. Patch adds a work around for the quirk and enables biphase decoding. Changes from v1: * rebased due to conflict with "img-ir/hw: Fix potential deadlock stopping timer" * spinlock taken in img_ir_suspend_timer * check for hw->stopping before handling quirks in img_ir_isr_hw * new memeber added to img_ir_priv_hw to save irq status over suspend Signed-off-by: Sifan Naeem --- drivers/media/rc/img-ir/img-ir-hw.c | 60 +++++++++++++++++++++++++++++++++-- drivers/media/rc/img-ir/img-ir-hw.h | 4 +++ 2 files changed, 61 insertions(+), 3 deletions(-) diff --git a/drivers/media/rc/img-ir/img-ir-hw.c b/drivers/media/rc/img-ir/img-ir-hw.c index 9cecda7..5c32f05 100644 --- a/drivers/media/rc/img-ir/img-ir-hw.c +++ b/drivers/media/rc/img-ir/img-ir-hw.c @@ -52,6 +52,11 @@ static struct img_ir_decoder *img_ir_decoders[] = { #define IMG_IR_QUIRK_CODE_BROKEN 0x1 /* Decode is broken */ #define IMG_IR_QUIRK_CODE_LEN_INCR 0x2 /* Bit length needs increment */ +/* + * The decoder generates rapid interrupts without actually having + * received any new data after an incomplete IR code is decoded. + */ +#define IMG_IR_QUIRK_CODE_IRQ 0x4 /* functions for preprocessing timings, ensuring max is set */ @@ -542,6 +547,7 @@ static void img_ir_set_decoder(struct img_ir_priv *priv, */ spin_unlock_irq(&priv->lock); del_timer_sync(&hw->end_timer); + del_timer_sync(&hw->suspend_timer); spin_lock_irq(&priv->lock); hw->stopping = false; @@ -861,6 +867,29 @@ static void img_ir_end_timer(unsigned long arg) spin_unlock_irq(&priv->lock); } +/* + * Timer function to re-enable the current protocol after it had been + * cleared when invalid interrupts were generated due to a quirk in the + * img-ir decoder. + */ +static void img_ir_suspend_timer(unsigned long arg) +{ + struct img_ir_priv *priv = (struct img_ir_priv *)arg; + + spin_lock_irq(&priv->lock); + /* + * Don't overwrite enabled valid/match IRQs if they have already been + * changed by e.g. a filter change. + */ + if ((priv->hw.quirk_suspend_irq & IMG_IR_IRQ_EDGE) == + img_ir_read(priv, IMG_IR_IRQ_ENABLE)) + img_ir_write(priv, IMG_IR_IRQ_ENABLE, + priv->hw.quirk_suspend_irq); + /* enable */ + img_ir_write(priv, IMG_IR_CONTROL, priv->hw.reg_timings.ctrl); + spin_unlock_irq(&priv->lock); +} + #ifdef CONFIG_COMMON_CLK static void img_ir_change_frequency(struct img_ir_priv *priv, struct clk_notifier_data *change) @@ -926,15 +955,38 @@ void img_ir_isr_hw(struct img_ir_priv *priv, u32 irq_status) if (!hw->decoder) return; + ct = hw->decoder->control.code_type; + ir_status = img_ir_read(priv, IMG_IR_STATUS); - if (!(ir_status & (IMG_IR_RXDVAL | IMG_IR_RXDVALD2))) + if (!(ir_status & (IMG_IR_RXDVAL | IMG_IR_RXDVALD2))) { + if (!(priv->hw.ct_quirks[ct] & IMG_IR_QUIRK_CODE_IRQ) || + hw->stopping) + return; + /* + * The below functionality is added as a work around to stop + * multiple Interrupts generated when an incomplete IR code is + * received by the decoder. + * The decoder generates rapid interrupts without actually + * having received any new data. After a single interrupt it's + * expected to clear up, but instead multiple interrupts are + * rapidly generated. only way to get out of this loop is to + * reset the control register after a short delay. + */ + img_ir_write(priv, IMG_IR_CONTROL, 0); + hw->quirk_suspend_irq = img_ir_read(priv, IMG_IR_IRQ_ENABLE); + img_ir_write(priv, IMG_IR_IRQ_ENABLE, + hw->quirk_suspend_irq & IMG_IR_IRQ_EDGE); + + /* Timer activated to re-enable the protocol. */ + mod_timer(&hw->suspend_timer, + jiffies + msecs_to_jiffies(5)); return; + } ir_status &= ~(IMG_IR_RXDVAL | IMG_IR_RXDVALD2); img_ir_write(priv, IMG_IR_STATUS, ir_status); len = (ir_status & IMG_IR_RXDLEN) >> IMG_IR_RXDLEN_SHIFT; /* some versions report wrong length for certain code types */ - ct = hw->decoder->control.code_type; if (hw->ct_quirks[ct] & IMG_IR_QUIRK_CODE_LEN_INCR) ++len; @@ -976,7 +1028,7 @@ static void img_ir_probe_hw_caps(struct img_ir_priv *priv) hw->ct_quirks[IMG_IR_CODETYPE_PULSELEN] |= IMG_IR_QUIRK_CODE_LEN_INCR; hw->ct_quirks[IMG_IR_CODETYPE_BIPHASE] - |= IMG_IR_QUIRK_CODE_BROKEN; + |= IMG_IR_QUIRK_CODE_IRQ; hw->ct_quirks[IMG_IR_CODETYPE_2BITPULSEPOS] |= IMG_IR_QUIRK_CODE_BROKEN; } @@ -995,6 +1047,8 @@ int img_ir_probe_hw(struct img_ir_priv *priv) /* Set up the end timer */ setup_timer(&hw->end_timer, img_ir_end_timer, (unsigned long)priv); + setup_timer(&hw->suspend_timer, img_ir_suspend_timer, + (unsigned long)priv); /* Register a clock notifier */ if (!IS_ERR(priv->clk)) { diff --git a/drivers/media/rc/img-ir/img-ir-hw.h b/drivers/media/rc/img-ir/img-ir-hw.h index beac3a6..b31ffc9 100644 --- a/drivers/media/rc/img-ir/img-ir-hw.h +++ b/drivers/media/rc/img-ir/img-ir-hw.h @@ -218,6 +218,7 @@ enum img_ir_mode { * @rdev: Remote control device * @clk_nb: Notifier block for clock notify events. * @end_timer: Timer until repeat timeout. + * @suspend_timer: Timer to re-enable protocol. * @decoder: Current decoder settings. * @enabled_protocols: Currently enabled protocols. * @clk_hz: Current core clock rate in Hz. @@ -228,12 +229,14 @@ enum img_ir_mode { * @stopping: Indicates that decoder is being taken down and timers * should not be restarted. * @suspend_irqen: Saved IRQ enable mask over suspend. + * @quirk_suspend_irq: Saved IRQ enable mask over quirk suspend timer. */ struct img_ir_priv_hw { unsigned int ct_quirks[4]; struct rc_dev *rdev; struct notifier_block clk_nb; struct timer_list end_timer; + struct timer_list suspend_timer; const struct img_ir_decoder *decoder; u64 enabled_protocols; unsigned long clk_hz; @@ -244,6 +247,7 @@ struct img_ir_priv_hw { enum img_ir_mode mode; bool stopping; u32 suspend_irqen; + u32 quirk_suspend_irq; }; static inline bool img_ir_hw_enabled(struct img_ir_priv_hw *hw) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/