phy: renesas: rcar-gen3-usb2: Set timing registers only once

phy-rcar-gen3-usb2 driver exports 4 PHYs. The timing registers are common
to all PHYs. There is no need to set them every time a PHY is i

phy: renesas: rcar-gen3-usb2: Set timing registers only once

phy-rcar-gen3-usb2 driver exports 4 PHYs. The timing registers are common
to all PHYs. There is no need to set them every time a PHY is initialized.
Set timing register only when the 1st PHY is initialized.

Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc: [email protected]
Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Reviewed-by: Lad Prabhakar <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

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phy: renesas: rcar-gen3-usb2: Assert PLL reset on PHY power off

Assert PLL reset on PHY power off. This saves power.

Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc:

phy: renesas: rcar-gen3-usb2: Assert PLL reset on PHY power off

Assert PLL reset on PHY power off. This saves power.

Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc: [email protected]
Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Reviewed-by: Lad Prabhakar <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

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phy: renesas: rcar-gen3-usb2: Lock around hardware registers and driver data

The phy-rcar-gen3-usb2 driver exposes four individual PHYs that are
requested and configured by PHY users. The struct phy

phy: renesas: rcar-gen3-usb2: Lock around hardware registers and driver data

The phy-rcar-gen3-usb2 driver exposes four individual PHYs that are
requested and configured by PHY users. The struct phy_ops APIs access the
same set of registers to configure all PHYs. Additionally, PHY settings can
be modified through sysfs or an IRQ handler. While some struct phy_ops APIs
are protected by a driver-wide mutex, others rely on individual
PHY-specific mutexes.

This approach can lead to various issues, including:
1/ the IRQ handler may interrupt PHY settings in progress, racing with
hardware configuration protected by a mutex lock
2/ due to msleep(20) in rcar_gen3_init_otg(), while a configuration thread
suspends to wait for the delay, another thread may try to configure
another PHY (with phy_init() + phy_power_on()); re-running the
phy_init() goes to the exact same configuration code, re-running the
same hardware configuration on the same set of registers (and bits)
which might impact the result of the msleep for the 1st configuring
thread
3/ sysfs can configure the hardware (though role_store()) and it can
still race with the phy_init()/phy_power_on() APIs calling into the
drivers struct phy_ops

To address these issues, add a spinlock to protect hardware register access
and driver private data structures (e.g., calls to
rcar_gen3_is_any_rphy_initialized()). Checking driver-specific data remains
necessary as all PHY instances share common settings. With this change,
the existing mutex protection is removed and the cleanup.h helpers are
used.

While at it, to keep the code simpler, do not skip
regulator_enable()/regulator_disable() APIs in
rcar_gen3_phy_usb2_power_on()/rcar_gen3_phy_usb2_power_off() as the
regulators enable/disable operations are reference counted anyway.

Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc: [email protected]
Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Reviewed-by: Lad Prabhakar <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

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phy: renesas: rcar-gen3-usb2: Move IRQ request in probe

Commit 08b0ad375ca6 ("phy: renesas: rcar-gen3-usb2: move IRQ registration
to init") moved the IRQ request operation from probe to
struct phy_o

phy: renesas: rcar-gen3-usb2: Move IRQ request in probe

Commit 08b0ad375ca6 ("phy: renesas: rcar-gen3-usb2: move IRQ registration
to init") moved the IRQ request operation from probe to
struct phy_ops::phy_init API to avoid triggering interrupts (which lead to
register accesses) while the PHY clocks (enabled through runtime PM APIs)
are not active. If this happens, it results in a synchronous abort.

One way to reproduce this issue is by enabling CONFIG_DEBUG_SHIRQ, which
calls free_irq() on driver removal.

Move the IRQ request and free operations back to probe, and take the
runtime PM state into account in IRQ handler. This commit is preparatory
for the subsequent fixes in this series.

Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Reviewed-by: Lad Prabhakar <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

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phy: renesas: rcar-gen3-usb2: Fix role detection on unbind/bind

It has been observed on the Renesas RZ/G3S SoC that unbinding and binding
the PHY driver leads to role autodetection failures. This is

phy: renesas: rcar-gen3-usb2: Fix role detection on unbind/bind

It has been observed on the Renesas RZ/G3S SoC that unbinding and binding
the PHY driver leads to role autodetection failures. This issue occurs when
PHY 3 is the first initialized PHY. PHY 3 does not have an interrupt
associated with the USB2_INT_ENABLE register (as
rcar_gen3_int_enable[3] = 0). As a result, rcar_gen3_init_otg() is called
to initialize OTG without enabling PHY interrupts.

To resolve this, add rcar_gen3_is_any_otg_rphy_initialized() and call it in
role_store(), role_show(), and rcar_gen3_init_otg(). At the same time,
rcar_gen3_init_otg() is only called when initialization for a PHY with
interrupt bits is in progress. As a result, the
struct rcar_gen3_phy::otg_initialized is no longer needed.

Fixes: 549b6b55b005 ("phy: renesas: rcar-gen3-usb2: enable/disable independent irqs")
Cc: [email protected]
Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Reviewed-by: Lad Prabhakar <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

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