mailbox: qcom-ipcc: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: fix incorrect num_chans counting

Breaking out early when a match is found leads to an incorrect num_chans
value when more than one ipcc mailbox channel is used by the same device.

Fixes: e9d50e4b4d04 ("mailbox: qcom-ipcc: Dynamic alloc for channel arrangement")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: flag IRQ NO_THREAD

PREEMPT_RT forces qcom-ipcc's handler to be threaded with interrupts
enabled, which triggers a warning in __handle_irq_event_percpu():
irq 173 handler irq_default_primary_handler+0x0/0x10 enabled interrupts
WARNING: CPU: 0 PID: 77 at kernel/irq/handle.c:161 __handle_irq_event_percpu+0x4c4/0x4d0

Mark it IRQF_NO_THREAD to avoid running the handler in a threaded
context with threadirqs or PREEMPT_RT enabled.

Signed-off-by: Eric Chanudet <echanude@redhat.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Fix -Wunused-function with CONFIG_PM_SLEEP=n

When CONFIG_PM_SLEEP is not set, there is a warning that
qcom_ipcc_pm_resume() is unused:

drivers/mailbox/qcom-ipcc.c:258:12: error: 'qcom_ipcc_pm_resume' defined but not used [-Werror=unused-function]
258 | static int qcom_ipcc_pm_resume(struct device *dev)
| ^~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

Commit 1a3c7bb08826 ("PM: core: Add new *_PM_OPS macros, deprecate old
ones") reworked the PM_OPS macros to avoid this problem. Use
NOIRQ_SYSTEM_SLEEP_PM_OPS directly so that qcom_ipcc_pm_resume() always
appears to be used to the compiler, even though it will be dead code
eliminated in the !CONFIG_PM_SLEEP case.

Fixes: c25f77899753 ("mailbox: qcom-ipcc: Log the pending interrupt during resume")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Log the pending interrupt during resume

Enable logging of the pending interrupt that triggered device wakeup. This
logging information helps to debug IRQs that cause periodic device wakeups
by printing the detailed information of pending IPCC interrupts.

Scenario: Device wakeup caused by Modem crash
Logs:
qcom-ipcc mailbox: virq: 182 triggered client-id: 2; signal-id: 2

From the IPCC bindings it can further be understood that the client here is
IPCC_CLIENT_MPSS and the signal was IPCC_MPROC_SIGNAL_SMP2P.

Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Prasad Sodagudi <quic_psodagud@quicinc.com>
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: correct kerneldoc

Correct kerneldoc warnings like:

drivers/mailbox/arm_mhu_db.c:47:
warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
drivers/mailbox/qcom-ipcc.c:58:
warning: Function parameter or member 'num_chans' not described in 'qcom_ipcc'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Support interrupt wake up from suspend

Use IRQF_NO_SUSPEND flag instead of enable_irq_wake to
support interrupt wake up from suspend.

Signed-off-by: Huang Yiwei <quic_hyiwei@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Support more IPCC instance

Since hardware is supporting multiple IPCC instance,
use ipcc_%d instead of ipcc as the irq name to support
in driver.

Signed-off-by: Huang Yiwei <quic_hyiwei@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Dynamic alloc for channel arrangement

Dynamic alloc for channel arrangement instead of static alloced
array, it is more flexible and can reduce memory usage.

Signed-off-by: Huang Yiwei <quic_hyiwei@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Enable loading QCOM_IPCC as a module

This patch enables the qcom_ipcc driver to be loaded as a
module. IPCC is fairly core to system, so as such it should
never be unloaded. It registers as a mailbox + irq controller
and the irq controller drivers in kernel are not supposed to
be unloaded as they don't have the visibility over the clients
consuming the irqs. Hence adding supress_bind_attrs to disable
bind/unbind via sysfs.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: qcom-ipcc: Fix IPCC mbox channel exhaustion

Fix IPCC (Inter-Processor Communication Controller) channel exhaustion by
setting the channel private data to NULL on mbox shutdown.

Err Logs:
remoteproc: MBA booted without debug policy, loading mpss
remoteproc: glink-edge: failed to acquire IPC channel
remoteproc: failed to probe subdevices for remoteproc: -16

Fixes: fa74a0257f45 ("mailbox: Add support for Qualcomm IPCC")
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Cc: stable@vger.kernel.org
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

mailbox: Add support for Qualcomm IPCC

Add support for the Inter-Processor Communication Controller (IPCC)
block from Qualcomm that coordinates the interrupts (inbound & outbound)
for Multiprocessor (MPROC), COMPUTE-Level0 (COMPUTE-L0) & COMPUTE-Level1
(COMPUTE-L1) protocols for the Application Processor Subsystem (APSS).

This driver is modeled as an irqchip+mailbox driver. The irqchip part
helps in receiving the interrupts from the IPCC clients such as modems,
DSPs, PCI-E etc... and forwards them to respective entities in APSS.

On the other hand, the mailbox part is used to send interrupts to the IPCC
clients from the entities of APSS.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[mani: moved to mailbox, added static mbox channels and cleanups]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>