From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Hugues Deschenes Subject: [PATCH v3 2/3] i2c-designware: Check component type register Date: Wed, 27 Jan 2010 14:19:51 -0500 Message-ID: <20100127191949.759985000@octasic.com> References: <20100127191949.575931000@octasic.com> Return-path: Content-Disposition: inline; filename=check_dw_component Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Ben Dooks , Baruch Siach , Jean-Hugues Deschenes List-Id: linux-i2c@vger.kernel.org Designware component type register is checked before attaching to the device. Signed-off-by: Jean-Hugues Deschenes --- drivers/i2c/busses/i2c-designware.c | 11 +++++++++++ 1 file changed, 11 insertions(+) Index: linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c =================================================================== --- linux-2.6_i2c.orig/drivers/i2c/busses/i2c-designware.c +++ linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c @@ -68,6 +68,7 @@ #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 @@ -709,6 +710,7 @@ static int __devinit dw_i2c_probe(struct 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); @@ -755,12 +757,19 @@ static int __devinit dw_i2c_probe(struct 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 */ --