diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/bus/imx-weim.c | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c index 1a0e0277a404..db74334ca5ef 100644 --- a/drivers/bus/imx-weim.c +++ b/drivers/bus/imx-weim.c @@ -46,8 +46,18 @@ static const struct imx_weim_devtype imx51_weim_devtype = { }; #define MAX_CS_REGS_COUNT 6 +#define MAX_CS_COUNT 6 #define OF_REG_SIZE 3 +struct cs_timing { + bool is_applied; + u32 regs[MAX_CS_REGS_COUNT]; +}; + +struct cs_timing_state { + struct cs_timing cs[MAX_CS_COUNT]; +}; + static const struct of_device_id weim_id_table[] = { /* i.MX1/21 */ { .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, }, @@ -112,15 +122,20 @@ err: } /* Parse and set the timing for this device. */ -static int __init weim_timing_setup(struct device_node *np, void __iomem *base, - const struct imx_weim_devtype *devtype) +static int __init weim_timing_setup(struct device *dev, + struct device_node *np, void __iomem *base, + const struct imx_weim_devtype *devtype, + struct cs_timing_state *ts) { u32 cs_idx, value[MAX_CS_REGS_COUNT]; int i, ret; int reg_idx, num_regs; + struct cs_timing *cst; if (WARN_ON(devtype->cs_regs_count > MAX_CS_REGS_COUNT)) return -EINVAL; + if (WARN_ON(devtype->cs_count > MAX_CS_COUNT)) + return -EINVAL; ret = of_property_read_u32_array(np, "fsl,weim-cs-timing", value, devtype->cs_regs_count); @@ -146,10 +161,23 @@ static int __init weim_timing_setup(struct device_node *np, void __iomem *base, if (cs_idx >= devtype->cs_count) return -EINVAL; + /* prevent re-configuring a CS that's already been configured */ + cst = &ts->cs[cs_idx]; + if (cst->is_applied && memcmp(value, cst->regs, + devtype->cs_regs_count * sizeof(u32))) { + dev_err(dev, "fsl,weim-cs-timing conflict on %pOF", np); + return -EINVAL; + } + /* set the timing for WEIM */ for (i = 0; i < devtype->cs_regs_count; i++) writel(value[i], base + cs_idx * devtype->cs_stride + i * 4); + if (!cst->is_applied) { + cst->is_applied = true; + memcpy(cst->regs, value, + devtype->cs_regs_count * sizeof(u32)); + } } return 0; @@ -163,6 +191,7 @@ static int __init weim_parse_dt(struct platform_device *pdev, const struct imx_weim_devtype *devtype = of_id->data; struct device_node *child; int ret, have_child = 0; + struct cs_timing_state ts = {}; if (devtype == &imx50_weim_devtype) { ret = imx_weim_gpr_setup(pdev); @@ -171,7 +200,7 @@ static int __init weim_parse_dt(struct platform_device *pdev, } for_each_available_child_of_node(pdev->dev.of_node, child) { - ret = weim_timing_setup(child, base, devtype); + ret = weim_timing_setup(&pdev->dev, child, base, devtype, &ts); if (ret) dev_warn(&pdev->dev, "%pOF set timing failed.\n", child); |