From: Wolfram Sang <wsa@the-dreams.de>
To: Ray Jui <ray.jui@broadcom.com>
Cc: Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
linux-i2c@vger.kernel.org, devicetree@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org,
bcm-kernel-feedback-list@broadcom.com,
Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>,
Shreesha Rajashekar <shreesha.rajashekar@broadcom.com>,
Michael Cheng <ccheng@broadcom.com>
Subject: Re: [PATCH v5 2/8] i2c: iproc: Add slave mode support
Date: Wed, 27 Mar 2019 23:14:52 +0100 [thread overview]
Message-ID: <20190327221452.GA15396@kunai> (raw)
In-Reply-To: <20190214175725.60462-3-ray.jui@broadcom.com>
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> +static void bcm_iproc_i2c_slave_init(
> + struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)
> +{
> + u32 val;
> +
> + if (need_reset) {
> + /* put controller in reset */
> + val = readl(iproc_i2c->base + CFG_OFFSET);
> + val |= BIT(CFG_RESET_SHIFT);
> + writel(val, iproc_i2c->base + CFG_OFFSET);
> +
> + /* wait 100 usec per spec */
> + udelay(100);
> +
> + /* bring controller out of reset */
> + val &= ~(BIT(CFG_RESET_SHIFT));
> + writel(val, iproc_i2c->base + CFG_OFFSET);
> + }
> +
> + /* flush TX/RX FIFOs */
> + val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
> + writel(val, iproc_i2c->base + S_FIFO_CTRL_OFFSET);
Will flushing FIFOs work when a slave is register while a master
transfer is on-going at the same time?
> +
> + /* RANDOM SLAVE STRETCH time - 20ms*/
What is a "random stretch time"? 20ms sounds like a lot. Also, missing
space before comment terminator.
> @@ -224,22 +473,25 @@ static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)
>
> /* put controller in reset */
> val = readl(iproc_i2c->base + CFG_OFFSET);
> - val |= 1 << CFG_RESET_SHIFT;
> - val &= ~(1 << CFG_EN_SHIFT);
> + val |= BIT(CFG_RESET_SHIFT);
> + val &= ~(BIT(CFG_EN_SHIFT));
> writel(val, iproc_i2c->base + CFG_OFFSET);
>
> /* wait 100 usec per spec */
> udelay(100);
>
> /* bring controller out of reset */
> - val &= ~(1 << CFG_RESET_SHIFT);
> + val &= ~(BIT(CFG_RESET_SHIFT));
> writel(val, iproc_i2c->base + CFG_OFFSET);
>
> /* flush TX/RX FIFOs and set RX FIFO threshold to zero */
> - val = (1 << M_FIFO_RX_FLUSH_SHIFT) | (1 << M_FIFO_TX_FLUSH_SHIFT);
> + val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));
> writel(val, iproc_i2c->base + M_FIFO_CTRL_OFFSET);
> /* disable all interrupts */
> - writel(0, iproc_i2c->base + IE_OFFSET);
> + val = readl(iproc_i2c->base + IE_OFFSET);
> + val &= ~(IE_M_ALL_INTERRUPT_MASK <<
> + IE_M_ALL_INTERRUPT_SHIFT);
> + writel(val, iproc_i2c->base + IE_OFFSET);
This block looks unrelated, but I won't be too strict here...
> + case M_CMD_STATUS_FIFO_UNDERRUN:
> + dev_dbg(iproc_i2c->device, "FIFO under-run\n");
> + return -ENXIO;
> +
> + case M_CMD_STATUS_RX_FIFO_FULL:
> + dev_dbg(iproc_i2c->device, "Master Rx FIFO full > 10ms\n");
> + return -ETIMEDOUT;
> +
... however, this looks really unrelated to me. This is about master
transmission, or?
Rest looks OK.
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next prev parent reply other threads:[~2019-03-27 22:14 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-14 17:57 [PATCH v5 0/8] iProc I2C slave mode and NIC mode Ray Jui
2019-02-14 17:57 ` [PATCH v5 1/8] i2c: iproc: Extend I2C read up to 255 bytes Ray Jui
2019-03-27 22:17 ` Wolfram Sang
2019-04-01 21:35 ` Ray Jui
2019-02-14 17:57 ` [PATCH v5 2/8] i2c: iproc: Add slave mode support Ray Jui
2019-03-27 22:14 ` Wolfram Sang [this message]
2019-03-27 22:41 ` Wolfram Sang
2019-04-01 21:33 ` Ray Jui
2019-04-02 8:24 ` Rayagonda Kokatanur
2019-04-02 9:01 ` Wolfram Sang
2019-02-14 17:57 ` [PATCH v5 3/8] dt-bindings: i2c: iproc: make 'interrupts' optional Ray Jui
2019-02-14 22:25 ` Rob Herring
2019-02-14 17:57 ` [PATCH v5 4/8] i2c: iproc: add polling support Ray Jui
2019-02-14 17:57 ` [PATCH v5 5/8] i2c: iproc: use wrapper for read/write access Ray Jui
2019-02-14 17:57 ` [PATCH v5 6/8] dt-bindings: i2c: iproc: add "brcm,iproc-nic-i2c" compatible string Ray Jui
2019-02-14 22:26 ` Rob Herring
2019-03-27 22:24 ` Wolfram Sang
2019-04-01 21:43 ` Ray Jui
2019-04-02 10:17 ` Wolfram Sang
2019-02-14 17:57 ` [PATCH v5 7/8] i2c: iproc: add NIC I2C support Ray Jui
2019-04-02 10:27 ` Wolfram Sang
2019-04-02 17:57 ` Ray Jui
2019-04-03 1:10 ` Ray Jui
2019-02-14 17:57 ` [PATCH v5 8/8] arm64: dts: Stingray: Add NIC i2c device node Ray Jui
2019-02-22 20:04 ` [PATCH v5 0/8] iProc I2C slave mode and NIC mode Ray Jui
2019-03-22 16:40 ` Florian Fainelli
2019-03-27 22:27 ` Wolfram Sang
2019-04-01 21:44 ` Ray Jui
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