From 4ff895bc8b90e30ff8e89ca7bc6666b229c77e5d Mon Sep 17 00:00:00 2001 From: Jean-Hugues Deschenes Date: Thu, 6 Oct 2011 11:26:26 -0700 Subject: [PATCH] i2c-designware: Check component type register Designware component type register is checked before attaching to the device. Signed-off-by: Jean-Hugues Deschenes Signed-off-by: Dirk Brandewie Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-designware.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c index 28335c3717d9..49386951f7fd 100644 --- a/drivers/i2c/busses/i2c-designware.c +++ b/drivers/i2c/busses/i2c-designware.c @@ -69,6 +69,7 @@ #define DW_IC_TXFLR 0x74 #define DW_IC_RXFLR 0x78 #define DW_IC_COMP_PARAM_1 0xf4 +#define DW_IC_COMP_TYPE 0xfc #define DW_IC_TX_ABRT_SOURCE 0x80 #define DW_IC_CON_MASTER 0x1 @@ -710,6 +711,7 @@ static int __devinit dw_i2c_probe(struct platform_device *pdev) struct i2c_adapter *adap; struct resource *mem, *ioarea; int irq, r; + u32 reg; /* NOTE: driver uses the static register mapping */ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -756,12 +758,19 @@ static int __devinit dw_i2c_probe(struct platform_device *pdev) r = -EBUSY; goto err_unuse_clocks; } - { - u32 param1 = dw_readl(dev, DW_IC_COMP_PARAM_1); - dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; - dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; + reg = dw_readl(dev, DW_IC_COMP_TYPE); + if (reg != 0x44570140) { + dev_err(&pdev->dev, "Unknown Synopsys component type: " + "0x%08x\n", reg); + r = -ENODEV; + goto err_iounmap; } + + reg = dw_readl(dev, DW_IC_COMP_PARAM_1); + dev->tx_fifo_depth = ((reg >> 16) & 0xff) + 1; + dev->rx_fifo_depth = ((reg >> 8) & 0xff) + 1; + i2c_dw_init(dev); dw_writel(dev, 0, DW_IC_INTR_MASK); /* disable IRQ */ -- 2.20.1