bus: mhi: core: Indexed MHI controller name

Today the MHI controller name is simply cloned from the underlying
bus device (its parent), that gives the following device structure
for e.g. a MHI/PCI controller:
devices/pci0000:00/0000:00:01.2/0000:02:00.0/0000:02:00.0
devices/pci0000:00/0000:00:01.2/0000:02:00.0/0000:02:00.0/0000:02:00.0_IPCR
...

That's quite misleading/confusing and can cause device registering
issues because of duplicate dev name (e.g. if a PCI device register
two different MHI instances).

This patch changes MHI core to create indexed mhi controller names
(mhi0, mhi1...) in the same way as other busses (i2c0, usb0...).

The previous example becomes:
devices/pci0000:00/0000:00:01.2/0000:02:00.0/mhi0
devices/pci0000:00/0000:00:01.2/0000:02:00.0/mhi0/mhi0_IPCR
...
 v2: move index field at the end of mhi_controller struct (before bool)
     to avoid breaking well packed alignment.

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 655d539c6808a070d80c2f35f4f4bcd734c0e9ca..1d6f7b6c1fcd27d98a8044a6d06673488fcaf5c7 100644 (file)
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -8,6 +8,7 @@
 #include <linux/device.h>
 #include <linux/dma-direction.h>
 #include <linux/dma-mapping.h>
+#include <linux/idr.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
 #include <linux/mhi.h>
@@ -18,6 +19,8 @@
 #include <linux/wait.h>
 #include "internal.h"
 
+static DEFINE_IDA(mhi_controller_ida);
+
 const char * const mhi_ee_str[MHI_EE_MAX] = {
        [MHI_EE_PBL] = "PBL",
        [MHI_EE_SBL] = "SBL",
@@ -940,6 +943,12 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
        mhi_cntrl->minor_version = (soc_info & SOC_HW_VERSION_MINOR_VER_BMSK) >>
                                        SOC_HW_VERSION_MINOR_VER_SHFT;
 
+       mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL);
+       if (mhi_cntrl->index < 0) {
+               ret = mhi_cntrl->index;
+               goto error_ida_alloc;
+       }
+
        /* Register controller with MHI bus */
        mhi_dev = mhi_alloc_device(mhi_cntrl);
        if (IS_ERR(mhi_dev)) {
@@ -950,8 +959,8 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
 
        mhi_dev->dev_type = MHI_DEVICE_CONTROLLER;
        mhi_dev->mhi_cntrl = mhi_cntrl;
-       dev_set_name(&mhi_dev->dev, "%s", dev_name(mhi_cntrl->cntrl_dev));
-       mhi_dev->name = dev_name(mhi_cntrl->cntrl_dev);
+       dev_set_name(&mhi_dev->dev, "mhi%d", mhi_cntrl->index);
+       mhi_dev->name = dev_name(&mhi_dev->dev);
 
        /* Init wakeup source */
        device_init_wakeup(&mhi_dev->dev, true);
@@ -970,6 +979,9 @@ error_add_dev:
        put_device(&mhi_dev->dev);
 
 error_alloc_dev:
+       ida_free(&mhi_controller_ida, mhi_cntrl->index);
+
+error_ida_alloc:
        kfree(mhi_cntrl->mhi_cmd);
 
 error_alloc_cmd:
@@ -1004,6 +1016,8 @@ void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
 
        device_del(&mhi_dev->dev);
        put_device(&mhi_dev->dev);
+
+       ida_free(&mhi_controller_ida, mhi_cntrl->index);
 }
 EXPORT_SYMBOL_GPL(mhi_unregister_controller);
 

diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
index 4eb93d8bea1d68dc55e0d2633efa0edfe826a8b8..702c31b6aefa7e4ee686ddf918a7b8add1177f4f 100644 (file)
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -331,7 +331,7 @@ void mhi_create_devices(struct mhi_controller *mhi_cntrl)
                /* Channel name is same for both UL and DL */
                mhi_dev->name = mhi_chan->name;
                dev_set_name(&mhi_dev->dev, "%s_%s",
-                            dev_name(mhi_cntrl->cntrl_dev),
+                            dev_name(&mhi_cntrl->mhi_dev->dev),
                             mhi_dev->name);
 
                /* Init wakeup source if available */

diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index d31efcf02ae712d79c3060ee2c81bf6a6ff89ae9..aa9757e71f1fc76b5f678cb2880f08a8069209c8 100644 (file)
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -348,6 +348,7 @@ struct mhi_controller_config {
  * @read_reg: Read a MHI register via the physical link (required)
  * @write_reg: Write a MHI register via the physical link (required)
  * @buffer_len: Bounce buffer length
+ * @index: Index of the MHI controller instance
  * @bounce_buf: Use of bounce buffer
  * @fbc_download: MHI host needs to do complete image transfer (optional)
  * @pre_init: MHI host needs to do pre-initialization before power up
@@ -438,6 +439,7 @@ struct mhi_controller {
                          u32 val);
 
        size_t buffer_len;
+       int index;
        bool bounce_buf;
        bool fbc_download;
        bool pre_init;