From: t.figa@samsung•com (Tomasz Figa)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 1/2 v3] i2c: exynos5: add support for HSI2C on Exynos5260 SoC
Date: Thu, 06 Feb 2014 14:31:16 +0100 [thread overview]
Message-ID: <52F38EA4.10805@samsung.com> (raw)
In-Reply-To: <1391688408-8077-1-git-send-email-ch.naveen@samsung.com>
Hi Naveen,
On 06.02.2014 13:06, Naveen Krishna Chatradhi wrote:
> This patch implements a variant struct to handle the differences
> (like fifo_depths) in the HSI2C modules across SoCs.
>
> Adds a new compatible to support HSI2C module on Exynos5260.
> Also resets the module as an init sequence (Needed by Exynos5260).
>
> Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung•com>
> ---
> Changes since v2:
> 1. Used variant struct as suggested by Tomasz Figa.
> 2. Change compatible strings from samsung,exynos5-hsi2c to
> samsung,exynos5250-hsi2c based on the first SoC to see the feature.
> 3. Using reset as init sequences.
> 4. Merged the 2 patches into one.
>
> .../devicetree/bindings/i2c/i2c-exynos5.txt | 8 ++-
> drivers/i2c/busses/i2c-exynos5.c | 64 ++++++++++++++++----
> 2 files changed, 58 insertions(+), 14 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt b/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt
> index 056732c..5bc4998 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt
> @@ -5,7 +5,11 @@ at various speeds ranging from 100khz to 3.4Mhz.
>
> Required properties:
> - compatible: value should be.
> - -> "samsung,exynos5-hsi2c", for i2c compatible with exynos5 hsi2c.
Device tree bindings need to be backwards compatible, so you need to
keep this compatible string supported, just marked as (DEPRECATED).
Driver-wise, it will use the same driver data / variant struct as
"samsung,exynos5250-hsi2c", just one more entry in OF match table is needed.
> + -> "samsung,exynos5250-hsi2c", for i2c compatible with HSI2C available
> + on Exynos5250 and Exynos5420 SoCs.
> + -> "samsung,exynos5260-hsi2c", for i2c compatible with HSI2C available
> + on Exynos5260 SoCs.
> +
> - reg: physical base address of the controller and length of memory mapped
> region.
> - interrupts: interrupt number to the cpu.
> @@ -26,7 +30,7 @@ Optional properties:
> Example:
>
> hsi2c at 12ca0000 {
> - compatible = "samsung,exynos5-hsi2c";
> + compatible = "samsung,exynos5250-hsi2c";
> reg = <0x12ca0000 0x100>;
> interrupts = <56>;
> clock-frequency = <100000>;
[snip]
> @@ -483,6 +514,7 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop)
> u32 i2c_auto_conf = 0;
> u32 fifo_ctl;
> unsigned long flags;
> + unsigned short trig_lvl;
>
> i2c_ctl = readl(i2c->regs + HSI2C_CTL);
> i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON);
> @@ -493,13 +525,19 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop)
>
> i2c_auto_conf = HSI2C_READ_WRITE;
>
> - fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(HSI2C_DEF_TXFIFO_LVL);
> + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ?
> + (i2c->variant->fifo_depth * 3/4) : i2c->msg->len;
> + fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(trig_lvl);
> +
This is a rather serious semantic change, that doesn't look to belong to
this patch. If this is needed, it should be done in a separate patch.
> int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN |
> HSI2C_INT_TRAILING_EN);
> } else {
> i2c_ctl |= HSI2C_TXCHON;
>
> - fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(HSI2C_DEF_RXFIFO_LVL);
> + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ?
> + (i2c->variant->fifo_depth * 1/4) : i2c->msg->len;
> + fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(trig_lvl);
> +
Ditto.
Best regards,
Tomasz
next prev parent reply other threads:[~2014-02-06 13:31 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1385100851-32254-1-git-send-email-ch.naveen@samsung.com>
2014-02-06 12:06 ` [PATCH 1/2 v3] i2c: exynos5: add support for HSI2C on Exynos5260 SoC Naveen Krishna Chatradhi
2014-02-06 13:31 ` Tomasz Figa [this message]
2014-02-06 13:50 ` Tomasz Figa
2014-02-07 10:17 ` Wolfram Sang
2014-02-07 10:21 ` Tomasz Figa
2014-02-07 4:43 ` [PATCH 2/2 v4] i2c: exynos5: configure fifo_depth based on HSI2C module variant Naveen Krishna Chatradhi
2014-03-12 19:20 ` Wolfram Sang
2014-04-28 6:35 ` Naveen Krishna Ch
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