Re: [PATCH v3 5/6] bus: Add Baikal-T1 APB-bus driver

[Arnd Bergmann <arnd@arndb.de>]

On Tue, May 26, 2020 at 2:59 PM Serge Semin
<Sergey.Semin@baikalelectronics.ru> wrote:
>
> Baikal-T1 AXI-APB bridge is used to access the SoC subsystem CSRs.
> IO requests are routed to this bus by means of the DW AMBA 3 AXI
> Interconnect. In case if an attempted APB transaction stays with no
> response for a pre-defined time an interrupt occurs and the bus gets
> freed for a next operation. This driver provides the interrupt handler
> to detect the erroneous address, prints an error message about the
> address fault, updates an errors counter. The counter and the APB-bus
> operations timeout can be accessed via corresponding sysfs nodes.
> A dedicated sysfs-node can be also used to artificially cause the
> bus errors described above.
>
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> Cc: Paul Burton <paulburton@kernel.org>
> Cc: Olof Johansson <olof@lixom.net>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: linux-mips@vger.kernel.org
> Cc: soc@kernel.org
> Cc: devicetree@vger.kernel.org
>
> ---

Applied with this fixup:

--- a/drivers/bus/bt1-apb.c
+++ b/drivers/bus/bt1-apb.c
@@ -16,6 +16,7 @@
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/nmi.h>
+#include <linux/of.h>
 #include <linux/regmap.h>
 #include <linux/clk.h>
 #include <linux/reset.h>
@@ -309,13 +310,13 @@ static ssize_t timeout_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(timeout);

-static int inject_error_show(struct device *dev, struct device_attribute *attr,
+static ssize_t inject_error_show(struct device *dev, struct
device_attribute *attr,
                             char *buf)
 {
        return scnprintf(buf, PAGE_SIZE, "Error injection: nodev irq\n");
 }

-static int inject_error_store(struct device *dev,
+static ssize_t inject_error_store(struct device *dev,
                              struct device_attribute *attr,
                              const char *data, size_t count)
 {