diff options
| -rw-r--r-- | drivers/char/hw_random/imx-rngc.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c index 92e93abcc9cc..50a8923d829a 100644 --- a/drivers/char/hw_random/imx-rngc.c +++ b/drivers/char/hw_random/imx-rngc.c @@ -18,12 +18,22 @@ #include <linux/completion.h> #include <linux/io.h> +#define RNGC_VER_ID 0x0000 #define RNGC_COMMAND 0x0004 #define RNGC_CONTROL 0x0008 #define RNGC_STATUS 0x000C #define RNGC_ERROR 0x0010 #define RNGC_FIFO 0x0014 +/* the fields in the ver id register */ +#define RNGC_TYPE_SHIFT 28 +#define RNGC_VER_MAJ_SHIFT 8 + +/* the rng_type field */ +#define RNGC_TYPE_RNGB 0x1 +#define RNGC_TYPE_RNGC 0x2 + + #define RNGC_CMD_CLR_ERR 0x00000020 #define RNGC_CMD_CLR_INT 0x00000010 #define RNGC_CMD_SEED 0x00000002 @@ -212,6 +222,8 @@ static int imx_rngc_probe(struct platform_device *pdev) struct imx_rngc *rngc; int ret; int irq; + u32 ver_id; + u8 rng_type; rngc = devm_kzalloc(&pdev->dev, sizeof(*rngc), GFP_KERNEL); if (!rngc) @@ -237,6 +249,17 @@ static int imx_rngc_probe(struct platform_device *pdev) if (ret) return ret; + ver_id = readl(rngc->base + RNGC_VER_ID); + rng_type = ver_id >> RNGC_TYPE_SHIFT; + /* + * This driver supports only RNGC and RNGB. (There's a different + * driver for RNGA.) + */ + if (rng_type != RNGC_TYPE_RNGC && rng_type != RNGC_TYPE_RNGB) { + ret = -ENODEV; + goto err; + } + ret = devm_request_irq(&pdev->dev, irq, imx_rngc_irq, 0, pdev->name, (void *)rngc); if (ret) { @@ -269,7 +292,10 @@ static int imx_rngc_probe(struct platform_device *pdev) goto err; } - dev_info(&pdev->dev, "Freescale RNGC registered.\n"); + dev_info(&pdev->dev, + "Freescale RNG%c registered (HW revision %d.%02d)\n", + rng_type == RNGC_TYPE_RNGB ? 'B' : 'C', + (ver_id >> RNGC_VER_MAJ_SHIFT) & 0xff, ver_id & 0xff); return 0; err: |