From abf60caf7dd59ef16e1a8b807e4f039bdaf979f2 Mon Sep 17 00:00:00 2001 From: Zhangfei Gao Date: Wed, 3 Apr 2013 10:49:58 +0800 Subject: i2c: designware-hs: add i2c delay 300ns workaround Signed-off-by: Zhangfei Gao --- arch/arm/boot/dts/hi3620.dtsi | 4 ++++ drivers/i2c/busses/i2c-designware-core.h | 1 + drivers/i2c/busses/i2c-designware-hs.c | 36 ++++++++++++++++++++++++++++++++ 3 files changed, 41 insertions(+) diff --git a/arch/arm/boot/dts/hi3620.dtsi b/arch/arm/boot/dts/hi3620.dtsi index dfe0b764f70..109d6f4b53d 100644 --- a/arch/arm/boot/dts/hi3620.dtsi +++ b/arch/arm/boot/dts/hi3620.dtsi @@ -1270,6 +1270,7 @@ &dma0 19>; /* write channel */ dma-names = "rx", "tx"; status = "disabled"; + delay-reg = <0 1>; }; i2c1: i2c@fcb09000 { @@ -1282,6 +1283,7 @@ dmas = <&dma0 20 /* read channel */ &dma0 21>; /* write channel */ dma-names = "rx", "tx"; + delay-reg = <0 2>; status = "disabled"; }; @@ -1290,6 +1292,7 @@ reg = <0xfcb0c000 0x1000>; interrupts = <0 62 4>; clocks = <&clk_i2c2>; + delay-reg = <0xc 4>; status = "disabled"; }; @@ -1298,6 +1301,7 @@ reg = <0xfcb0d000 0x1000>; interrupts = <0 63 4>; clocks = <&clk_i2c3>; + delay-reg = <0xc 5>; status = "disabled"; }; diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index f4efd1ac419..05ab3e11cad 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -88,6 +88,7 @@ struct dw_i2c_dev { u32 master_cfg; unsigned int tx_fifo_depth; unsigned int rx_fifo_depth; + void *priv; }; #define ACCESS_SWAP 0x00000001 diff --git a/drivers/i2c/busses/i2c-designware-hs.c b/drivers/i2c/busses/i2c-designware-hs.c index d986a12f5bb..9b8a3b6faa3 100644 --- a/drivers/i2c/busses/i2c-designware-hs.c +++ b/drivers/i2c/busses/i2c-designware-hs.c @@ -24,8 +24,16 @@ #include #include #include +#include #include "i2c-designware-core.h" +static void __iomem *pctrl; + +struct hs_i2c_priv_data { + u32 delay_off; + u32 delay_bit; +}; + static struct i2c_algorithm hs_i2c_dw_algo = { .master_xfer = i2c_dw_xfer, .functionality = i2c_dw_func, @@ -41,12 +49,22 @@ static int hs_dw_i2c_probe(struct platform_device *pdev) struct i2c_adapter *adap; struct resource *iores; struct pinctrl *pinctrl; + struct device_node *node; + u32 data[2]; + struct hs_i2c_priv_data *priv; int r; d = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); if (!d) return -ENOMEM; + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) { + dev_err(&pdev->dev, "mem alloc failed for private data\n"); + return -ENOMEM; + } + d->priv = priv; + /* NOTE: driver uses the static register mapping */ iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!iores) @@ -56,6 +74,20 @@ static int hs_dw_i2c_probe(struct platform_device *pdev) if (!d->base) return -EADDRNOTAVAIL; + if (!pctrl) { + node = of_find_compatible_node(NULL, NULL, + "hisilicon,pctrl"); + if (node) + pctrl = of_iomap(node, 0); + } + of_property_read_u32_array(pdev->dev.of_node, "delay-reg", &data[0], 2); + priv->delay_off = data[0]; + priv->delay_bit = data[1]; + + if (pctrl) + writel(BIT((priv->delay_bit) << 16) | BIT(priv->delay_bit), + pctrl + priv->delay_off); + d->irq = platform_get_irq(pdev, 0); if (d->irq < 0) { dev_err(&pdev->dev, "no irq resource?\n"); @@ -132,6 +164,10 @@ err: static int hs_dw_i2c_remove(struct platform_device *pdev) { struct dw_i2c_dev *d = platform_get_drvdata(pdev); + struct hs_i2c_priv_data *priv = d->priv; + + if (pctrl) + writel(BIT((priv->delay_bit) << 16), pctrl + priv->delay_off); platform_set_drvdata(pdev, NULL); i2c_del_adapter(&d->adapter); -- cgit v1.2.3