diff options
Diffstat (limited to 'target/linux/layerscape/patches-4.4/7193-staging-fsl-mc-add-device-binding-path-driver_overri.patch')
| -rw-r--r-- | target/linux/layerscape/patches-4.4/7193-staging-fsl-mc-add-device-binding-path-driver_overri.patch | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-4.4/7193-staging-fsl-mc-add-device-binding-path-driver_overri.patch b/target/linux/layerscape/patches-4.4/7193-staging-fsl-mc-add-device-binding-path-driver_overri.patch new file mode 100644 index 0000000000..60d294a1da --- /dev/null +++ b/target/linux/layerscape/patches-4.4/7193-staging-fsl-mc-add-device-binding-path-driver_overri.patch @@ -0,0 +1,111 @@ +From 0bda83c15b2ecfc45fac0656df15d4f4fa65afa9 Mon Sep 17 00:00:00 2001 +From: Bharat Bhushan <bharat.bhushan@freescale.com> +Date: Wed, 18 Mar 2015 17:32:59 -0500 +Subject: [PATCH 193/226] staging: fsl-mc: add device binding path + 'driver_override' + +This patch is required for vfio-fsl-mc meta driver to successfully bind +layerscape container devices for device passthrough. This patch adds +a mechanism to allow a layerscape device to specify a driver rather than +a layerscape driver provide a device match. + +This patch is based on following proposed patches for PCI and platform devices +- https://lkml.org/lkml/2014/4/8/571 :- For Platform devices +- http://lists-archives.com/linux-kernel/28030441-pci-introduce-new-device-binding-path-using-pci_dev-driver_override.html :- For PCI devices + +Example to allow a device (dprc.1) to specifically bind +with driver (vfio-fsl-mc):- +- echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.1/driver_override +- echo dprc.1 > /sys/bus/fsl-mc/drivers/fsl_mc_dprc/unbind +- echo dprc.1 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind + +Signed-off-by: J. German Rivera <German.Rivera@freescale.com> +(Stuart: resolved merge conflicts) +Signed-off-by: Stuart Yoder <stuart.yoder@nxp.com> +--- + drivers/staging/fsl-mc/bus/mc-bus.c | 53 +++++++++++++++++++++++++++++++++++ + 1 file changed, 53 insertions(+) + +--- a/drivers/staging/fsl-mc/bus/mc-bus.c ++++ b/drivers/staging/fsl-mc/bus/mc-bus.c +@@ -42,6 +42,12 @@ static int fsl_mc_bus_match(struct devic + if (WARN_ON(!fsl_mc_bus_exists())) + goto out; + ++ /* When driver_override is set, only bind to the matching driver */ ++ if (mc_dev->driver_override) { ++ found = !strcmp(mc_dev->driver_override, mc_drv->driver.name); ++ goto out; ++ } ++ + if (!mc_drv->match_id_table) + goto out; + +@@ -96,6 +102,50 @@ static ssize_t modalias_show(struct devi + } + static DEVICE_ATTR_RO(modalias); + ++static ssize_t driver_override_store(struct device *dev, ++ struct device_attribute *attr, ++ const char *buf, size_t count) ++{ ++ struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); ++ const char *driver_override, *old = mc_dev->driver_override; ++ char *cp; ++ ++ if (WARN_ON(dev->bus != &fsl_mc_bus_type)) ++ return -EINVAL; ++ ++ if (count > PATH_MAX) ++ return -EINVAL; ++ ++ driver_override = kstrndup(buf, count, GFP_KERNEL); ++ if (!driver_override) ++ return -ENOMEM; ++ ++ cp = strchr(driver_override, '\n'); ++ if (cp) ++ *cp = '\0'; ++ ++ if (strlen(driver_override)) { ++ mc_dev->driver_override = driver_override; ++ } else { ++ kfree(driver_override); ++ mc_dev->driver_override = NULL; ++ } ++ ++ kfree(old); ++ ++ return count; ++} ++ ++static ssize_t driver_override_show(struct device *dev, ++ struct device_attribute *attr, char *buf) ++{ ++ struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); ++ ++ return sprintf(buf, "%s\n", mc_dev->driver_override); ++} ++ ++static DEVICE_ATTR_RW(driver_override); ++ + static ssize_t rescan_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +@@ -127,6 +177,7 @@ static DEVICE_ATTR_WO(rescan); + static struct attribute *fsl_mc_dev_attrs[] = { + &dev_attr_modalias.attr, + &dev_attr_rescan.attr, ++ &dev_attr_driver_override.attr, + NULL, + }; + +@@ -677,6 +728,8 @@ void fsl_mc_device_remove(struct fsl_mc_ + } + } + ++ kfree(mc_dev->driver_override); ++ mc_dev->driver_override = NULL; + if (mc_bus) + devm_kfree(mc_dev->dev.parent, mc_bus); + else |