i2c-designware: Check component type register
Designware component type register is checked before attaching to the device.
Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c
index 28335c3..4938695 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 @@
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 @@
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 */