diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-fsi | 8 | ||||
| -rw-r--r-- | drivers/fsi/fsi-master-aspeed.c | 43 |
2 files changed, 51 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-fsi b/Documentation/ABI/testing/sysfs-bus-fsi index 320697bdf41d..d148214181a1 100644 --- a/Documentation/ABI/testing/sysfs-bus-fsi +++ b/Documentation/ABI/testing/sysfs-bus-fsi @@ -36,3 +36,11 @@ Contact: linux-fsi@lists.ozlabs.org Description: Provides a means of reading/writing a 32 bit value from/to a specified FSI bus address. + +What: /sys/bus/platform/devices/../cfam_reset +Date: Sept 2020 +KernelVersion: 5.10 +Contact: linux-fsi@lists.ozlabs.org +Description: + Provides a means of resetting the cfam that is attached to the + FSI device. diff --git a/drivers/fsi/fsi-master-aspeed.c b/drivers/fsi/fsi-master-aspeed.c index 2531e826ba8b..c006ec008a1a 100644 --- a/drivers/fsi/fsi-master-aspeed.c +++ b/drivers/fsi/fsi-master-aspeed.c @@ -22,6 +22,7 @@ struct fsi_master_aspeed { struct device *dev; void __iomem *base; struct clk *clk; + struct gpio_desc *cfam_reset_gpio; }; #define to_fsi_master_aspeed(m) \ @@ -425,6 +426,43 @@ static int aspeed_master_init(struct fsi_master_aspeed *aspeed) return 0; } +static ssize_t cfam_reset_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fsi_master_aspeed *aspeed = dev_get_drvdata(dev); + + gpiod_set_value(aspeed->cfam_reset_gpio, 1); + usleep_range(900, 1000); + gpiod_set_value(aspeed->cfam_reset_gpio, 0); + + return count; +} + +static DEVICE_ATTR(cfam_reset, 0200, NULL, cfam_reset_store); + +static int setup_cfam_reset(struct fsi_master_aspeed *aspeed) +{ + struct device *dev = aspeed->dev; + struct gpio_desc *gpio; + int rc; + + gpio = devm_gpiod_get_optional(dev, "cfam-reset", GPIOD_OUT_LOW); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + if (!gpio) + return 0; + + aspeed->cfam_reset_gpio = gpio; + + rc = device_create_file(dev, &dev_attr_cfam_reset); + if (rc) { + devm_gpiod_put(dev, gpio); + return rc; + } + + return 0; +} + static int tacoma_cabled_fsi_fixup(struct device *dev) { struct gpio_desc *routing_gpio, *mux_gpio; @@ -507,6 +545,11 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev) return rc; } + rc = setup_cfam_reset(aspeed); + if (rc) { + dev_err(&pdev->dev, "CFAM reset GPIO setup failed\n"); + } + writel(0x1, aspeed->base + OPB_CLK_SYNC); writel(OPB1_XFER_ACK_EN | OPB0_XFER_ACK_EN, aspeed->base + OPB_IRQ_MASK); |