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From: Douglas Anderson <dianders@chromium.org>
To: Mark Brown <broonie@kernel.org>
Cc: Alok Chauhan <alokc@codeaurora.org>,
	skakit@codeaurora.org, swboyd@chromium.org,
	Douglas Anderson <dianders@chromium.org>,
	Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-spi@vger.kernel.org
Subject: [PATCH v3 1/5] spi: spi-geni-qcom: No need for irqsave variant of spinlock calls
Date: Tue, 16 Jun 2020 03:40:46 -0700	[thread overview]
Message-ID: <20200616034044.v3.1.Ic50cccdf27d42420a63485082f8b5bf86ed1a2b6@changeid> (raw)
In-Reply-To: <20200616104050.84764-1-dianders@chromium.org>

The driver locks its locks in two places.

In the first usage of the lock the function doing the locking already
has a sleeping call and thus we know we can't be called from interrupt
context.  That means we can use the "spin_lock_irq" variant of the
function.

In the second usage of the lock the function is the interrupt handler
and we know interrupt handlers are called with interrupts disabled.
That means we can use the "spin_lock" variant of the function.

This patch is expected to be a no-op and is just a cleanup / slight
optimization.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

Changes in v3:
- ("spi: spi-geni-qcom: No need for irqsave variant...") new for v3

Changes in v2: None

 drivers/spi/spi-geni-qcom.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index c3972424af71..c7d2c7e45b3f 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -122,23 +122,23 @@ static void handle_fifo_timeout(struct spi_master *spi,
 				struct spi_message *msg)
 {
 	struct spi_geni_master *mas = spi_master_get_devdata(spi);
-	unsigned long time_left, flags;
+	unsigned long time_left;
 	struct geni_se *se = &mas->se;
 
-	spin_lock_irqsave(&mas->lock, flags);
+	spin_lock_irq(&mas->lock);
 	reinit_completion(&mas->xfer_done);
 	mas->cur_mcmd = CMD_CANCEL;
 	geni_se_cancel_m_cmd(se);
 	writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
-	spin_unlock_irqrestore(&mas->lock, flags);
+	spin_unlock_irq(&mas->lock);
 	time_left = wait_for_completion_timeout(&mas->xfer_done, HZ);
 	if (time_left)
 		return;
 
-	spin_lock_irqsave(&mas->lock, flags);
+	spin_lock_irq(&mas->lock);
 	reinit_completion(&mas->xfer_done);
 	geni_se_abort_m_cmd(se);
-	spin_unlock_irqrestore(&mas->lock, flags);
+	spin_unlock_irq(&mas->lock);
 	time_left = wait_for_completion_timeout(&mas->xfer_done, HZ);
 	if (!time_left)
 		dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
@@ -477,12 +477,11 @@ static irqreturn_t geni_spi_isr(int irq, void *data)
 	struct spi_geni_master *mas = spi_master_get_devdata(spi);
 	struct geni_se *se = &mas->se;
 	u32 m_irq;
-	unsigned long flags;
 
 	if (mas->cur_mcmd == CMD_NONE)
 		return IRQ_NONE;
 
-	spin_lock_irqsave(&mas->lock, flags);
+	spin_lock(&mas->lock);
 	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
 
 	if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
@@ -524,7 +523,7 @@ static irqreturn_t geni_spi_isr(int irq, void *data)
 	}
 
 	writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
-	spin_unlock_irqrestore(&mas->lock, flags);
+	spin_unlock(&mas->lock);
 	return IRQ_HANDLED;
 }
 
-- 
2.27.0.290.gba653c62da-goog


  reply	other threads:[~2020-06-16 10:41 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-16 10:40 [PATCH v3 0/5] spi: spi-geni-qcom: Fixes / perf improvements Douglas Anderson
2020-06-16 10:40 ` Douglas Anderson [this message]
2020-06-17 20:24   ` [PATCH v3 1/5] spi: spi-geni-qcom: No need for irqsave variant of spinlock calls Stephen Boyd
2020-06-16 10:40 ` [PATCH v3 2/5] spi: spi-geni-qcom: Mo' betta locking Douglas Anderson
2020-06-17 20:53   ` Stephen Boyd
2020-06-17 21:19     ` Doug Anderson
2020-06-18  0:47       ` Stephen Boyd
2020-06-16 10:40 ` [PATCH v3 3/5] spi: spi-geni-qcom: Check for error IRQs Douglas Anderson
2020-06-17 20:54   ` Stephen Boyd
2020-06-16 10:40 ` [PATCH v3 4/5] spi: spi-geni-qcom: Actually use our FIFO Douglas Anderson
2020-06-17 20:56   ` Stephen Boyd
2020-06-16 10:40 ` [PATCH v3 5/5] spi: spi-geni-qcom: Don't keep a local state variable Douglas Anderson
2020-06-17 21:16   ` Stephen Boyd
2020-06-18 15:05     ` Doug Anderson
2020-06-18 16:48 ` [PATCH v3 0/5] spi: spi-geni-qcom: Fixes / perf improvements Mark Brown

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