On Thu, Jan 09, 2020 at 01:30:15PM +0200, Andy Shevchenko wrote:
> On Wed, Jan 08, 2020 at 02:41:39PM +0300, Mika Westerberg wrote:
> > The current SCU IPC API has been operating on a single instance and
> > there has been no way to pin the providing module in place when the SCU
> > IPC is in use.
> >
> > This implements a new API that takes the SCU IPC instance as first
> > parameter (NULL means the single instance is being used). The SCU IPC
> > instance can be retrieved by calling new function
> > intel_scu_ipc_dev_get() that take care of pinning the providing module
> > in place as long as intel_scu_ipc_dev_put() is not called.
> >
> > The old API is left there to support existing users which cannot be
> > converted easily but it is put to a separate header that is subject to
> > be removed eventually. Subsequent patches will convert most of the users
> > to the new API.
>
> Few minor comments below. After addressing them,
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Thanks!
> >
> > Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> > ---
> > arch/x86/include/asm/intel_scu_ipc.h | 74 +++----
> > arch/x86/include/asm/intel_scu_ipc_legacy.h | 76 +++++++
> > drivers/platform/x86/intel_scu_ipc.c | 228 +++++++++++++++-----
> > drivers/platform/x86/intel_scu_pcidrv.c | 7 +-
> > 4 files changed, 291 insertions(+), 94 deletions(-)
> > create mode 100644 arch/x86/include/asm/intel_scu_ipc_legacy.h
> >
> > diff --git a/arch/x86/include/asm/intel_scu_ipc.h b/arch/x86/include/asm/intel_scu_ipc.h
> > index 405c47bf0965..9895b60386c5 100644
> > --- a/arch/x86/include/asm/intel_scu_ipc.h
> > +++ b/arch/x86/include/asm/intel_scu_ipc.h
> > @@ -1,8 +1,6 @@
> > /* SPDX-License-Identifier: GPL-2.0 */
> > #ifndef _ASM_X86_INTEL_SCU_IPC_H_
> > -#define _ASM_X86_INTEL_SCU_IPC_H_
> > -
> > -#include <linux/notifier.h>
> > +#define _ASM_X86_INTEL_SCU_IPC_H_
> >
> > #define IPCMSG_INDIRECT_READ 0x02
> > #define IPCMSG_INDIRECT_WRITE 0x05
> > @@ -20,6 +18,7 @@
> > #define IPC_CMD_VRTC_SETALARM 2 /* Set alarm */
> >
> > struct device;
> > +struct intel_scu_ipc_dev;
> >
> > /**
> > * struct intel_scu_ipc_pdata - Platform data for SCU IPC
> > @@ -31,47 +30,38 @@ struct intel_scu_ipc_pdata {
> > int irq;
> > };
> >
> > -int intel_scu_ipc_probe(struct device *dev,
> > - const struct intel_scu_ipc_pdata *pdata);
> > -
> > -/* Read single register */
> > -int intel_scu_ipc_ioread8(u16 addr, u8 *data);
> > -
> > -/* Read a vector */
> > -int intel_scu_ipc_readv(u16 *addr, u8 *data, int len);
> > -
> > -/* Write single register */
> > -int intel_scu_ipc_iowrite8(u16 addr, u8 data);
> > -
> > -/* Write a vector */
> > -int intel_scu_ipc_writev(u16 *addr, u8 *data, int len);
> > -
> > -/* Update single register based on the mask */
> > -int intel_scu_ipc_update_register(u16 addr, u8 data, u8 mask);
> > -
> > -/* Issue commands to the SCU with or without data */
> > -int intel_scu_ipc_simple_command(int cmd, int sub);
> > -int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
> > - u32 *out, int outlen);
> > -
> > -extern struct blocking_notifier_head intel_scu_notifier;
> > -
> > -static inline void intel_scu_notifier_add(struct notifier_block *nb)
> > -{
> > - blocking_notifier_chain_register(&intel_scu_notifier, nb);
> > -}
> > -
> > -static inline void intel_scu_notifier_remove(struct notifier_block *nb)
> > -{
> > - blocking_notifier_chain_unregister(&intel_scu_notifier, nb);
> > -}
> > -
> > -static inline int intel_scu_notifier_post(unsigned long v, void *p)
> > +struct intel_scu_ipc_dev *
> > +intel_scu_ipc_probe(struct device *dev, const struct intel_scu_ipc_pdata *pdata);
> > +
> > +struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void);
> > +void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu);
> > +struct intel_scu_ipc_dev *devm_intel_scu_ipc_dev_get(struct device *dev);
> > +
> > +int intel_scu_ipc_dev_ioread8(struct intel_scu_ipc_dev *scu, u16 addr,
> > + u8 *data);
> > +int intel_scu_ipc_dev_iowrite8(struct intel_scu_ipc_dev *scu, u16 addr,
> > + u8 data);
> > +int intel_scu_ipc_dev_readv(struct intel_scu_ipc_dev *scu, u16 *addr,
> > + u8 *data, size_t len);
> > +int intel_scu_ipc_dev_writev(struct intel_scu_ipc_dev *scu, u16 *addr,
> > + u8 *data, size_t len);
>
> + blank line?
OK
> > +int intel_scu_ipc_dev_update(struct intel_scu_ipc_dev *scu, u16 addr, u8 data,
> > + u8 mask);
>
> Perhaps move u8 data on the next line to be (slightly) consistent with above.
OK
> > +
> > +int intel_scu_ipc_dev_simple_command(struct intel_scu_ipc_dev *scu, int cmd,
> > + int sub);
> > +int intel_scu_ipc_dev_command_with_size(struct intel_scu_ipc_dev *scu, int cmd,
> > + int sub, const void *in, size_t inlen,
> > + size_t size, void *out, size_t outlen);
> > +
> > +static inline int intel_scu_ipc_dev_command(struct intel_scu_ipc_dev *scu, int cmd,
> > + int sub, const void *in, size_t inlen,
> > + void *out, size_t outlen)
> > {
> > - return blocking_notifier_call_chain(&intel_scu_notifier, v, p);
> > + return intel_scu_ipc_dev_command_with_size(scu, cmd, sub, in, inlen,
> > + inlen, out, outlen);
> > }
> >
> > -#define SCU_AVAILABLE 1
> > -#define SCU_DOWN 2
> > +#include <asm/intel_scu_ipc_legacy.h>
> >
> > #endif
> > diff --git a/arch/x86/include/asm/intel_scu_ipc_legacy.h b/arch/x86/include/asm/intel_scu_ipc_legacy.h
> > new file mode 100644
> > index 000000000000..3399ea8eea48
> > --- /dev/null
> > +++ b/arch/x86/include/asm/intel_scu_ipc_legacy.h
> > @@ -0,0 +1,76 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef _ASM_X86_INTEL_SCU_IPC_LEGACY_H_
> > +#define _ASM_X86_INTEL_SCU_IPC_LEGACY_H_
> > +
> > +#include <linux/notifier.h>
> > +
> > +/* Don't call these in new code - they will be removed eventually */
> > +
> > +/* Read single register */
> > +static inline int intel_scu_ipc_ioread8(u16 addr, u8 *data)
> > +{
> > + return intel_scu_ipc_dev_ioread8(NULL, addr, data);
> > +}
> > +
> > +/* Read a vector */
> > +static inline int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
> > +{
> > + return intel_scu_ipc_dev_readv(NULL, addr, data, len);
> > +}
> > +
> > +/* Write single register */
> > +static inline int intel_scu_ipc_iowrite8(u16 addr, u8 data)
> > +{
> > + return intel_scu_ipc_dev_iowrite8(NULL, addr, data);
> > +}
> > +
> > +/* Write a vector */
> > +static inline int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
> > +{
> > + return intel_scu_ipc_dev_writev(NULL, addr, data, len);
> > +}
> > +
> > +/* Update single register based on the mask */
> > +static inline int intel_scu_ipc_update_register(u16 addr, u8 data, u8 mask)
> > +{
> > + return intel_scu_ipc_dev_update(NULL, addr, data, mask);
> > +}
> > +
> > +/* Issue commands to the SCU with or without data */
> > +static inline int intel_scu_ipc_simple_command(int cmd, int sub)
> > +{
> > + return intel_scu_ipc_dev_simple_command(NULL, cmd, sub);
> > +}
> > +
> > +static inline int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
> > + u32 *out, int outlen)
> > +{
> > + /* New API takes both inlen and outlen as bytes so convert here */
> > + size_t inbytes = inlen * sizeof(u32);
> > + size_t outbytes = outlen * sizeof(u32);
> > +
> > + return intel_scu_ipc_dev_command_with_size(NULL, cmd, sub, in, inbytes,
> > + inlen, out, outbytes);
> > +}
> > +
> > +extern struct blocking_notifier_head intel_scu_notifier;
> > +
> > +static inline void intel_scu_notifier_add(struct notifier_block *nb)
> > +{
> > + blocking_notifier_chain_register(&intel_scu_notifier, nb);
> > +}
> > +
> > +static inline void intel_scu_notifier_remove(struct notifier_block *nb)
> > +{
> > + blocking_notifier_chain_unregister(&intel_scu_notifier, nb);
> > +}
> > +
> > +static inline int intel_scu_notifier_post(unsigned long v, void *p)
> > +{
> > + return blocking_notifier_call_chain(&intel_scu_notifier, v, p);
> > +}
> > +
> > +#define SCU_AVAILABLE 1
> > +#define SCU_DOWN 2
> > +
> > +#endif
> > diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c
> > index b1ac381bb7dd..cc29f504adcf 100644
> > --- a/drivers/platform/x86/intel_scu_ipc.c
> > +++ b/drivers/platform/x86/intel_scu_ipc.c
> > @@ -19,6 +19,7 @@
> > #include <linux/init.h>
> > #include <linux/interrupt.h>
> > #include <linux/io.h>
> > +#include <linux/module.h>
> >
> > #include <asm/intel_scu_ipc.h>
> >
> > @@ -77,6 +78,99 @@ static struct intel_scu_ipc_dev ipcdev; /* Only one for now */
> >
> > static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
> >
> > +/**
> > + * intel_scu_ipc_dev_get() - Get SCU IPC instance
> > + *
> > + * The recommended new API takes SCU IPC instance as parameter and this
> > + * function can be called by driver to get the instance. This also makes
> > + * sure the driver providing the IPC functionality cannot be unloaded
> > + * while the caller has the intance.
> > + *
> > + * Call intel_scu_ipc_dev_put() to release the instance.
> > + *
> > + * Returns %NULL if SCU IPC is not currently available.
> > + */
> > +struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void)
> > +{
> > + struct intel_scu_ipc_dev *scu = &ipcdev;
> > +
> > + mutex_lock(&ipclock);
> > + if (!scu->dev)
> > + goto err_unlock;
> > + if (!try_module_get(scu->dev->driver->owner))
> > + goto err_unlock;
> > + mutex_unlock(&ipclock);
> > + return scu;
> > +
> > +err_unlock:
> > + mutex_unlock(&ipclock);
> > + return NULL;
> > +}
> > +EXPORT_SYMBOL_GPL(intel_scu_ipc_dev_get);
> > +
> > +/**
> > + * intel_scu_ipc_dev_put() - Put SCU IPC instance
> > + * @scu: SCU IPC instance
> > + *
> > + * This function releases the SCU IPC instance retrieved from
> > + * intel_scu_ipc_dev_get() and allows the driver providing IPC to be
> > + * unloaded.
> > + */
> > +void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu)
> > +{
> > + mutex_lock(&ipclock);
> > + if (scu->dev)
> > + module_put(scu->dev->driver->owner);
> > + mutex_unlock(&ipclock);
> > +}
> > +EXPORT_SYMBOL_GPL(intel_scu_ipc_dev_put);
> > +
> > +struct intel_scu_ipc_devres {
> > + struct intel_scu_ipc_dev *scu;
> > +};
> > +
> > +static void devm_intel_scu_ipc_dev_release(struct device *dev, void *res)
> > +{
> > + struct intel_scu_ipc_devres *devres = res;
> > + struct intel_scu_ipc_dev *scu = devres->scu;
> > +
> > + intel_scu_ipc_dev_put(scu);
> > +}
> > +
> > +/**
> > + * devm_intel_scu_ipc_dev_get() - Allocate managed SCU IPC device
> > + * @dev: Device requesting the SCU IPC device
> > + *
> > + * The recommended new API takes SCU IPC instance as parameter and this
> > + * function can be called by driver to get the instance. This also makes
> > + * sure the driver providing the IPC functionality cannot be unloaded
> > + * while the caller has the intance.
> > + *
> > + * Returns %NULL if SCU IPC is not currently available.
> > + */
> > +struct intel_scu_ipc_dev *devm_intel_scu_ipc_dev_get(struct device *dev)
> > +{
> > + struct intel_scu_ipc_devres *devres;
> > + struct intel_scu_ipc_dev *scu;
> > +
> > + devres = devres_alloc(devm_intel_scu_ipc_dev_release, sizeof(*devres),
> > + GFP_KERNEL);
> > + if (!devres)
> > + return NULL;
> > +
> > + scu = intel_scu_ipc_dev_get();
> > + if (!scu) {
> > + devres_free(devres);
> > + return NULL;
> > + }
> > +
> > + devres->scu = scu;
> > + devres_add(dev, devres);
> > +
> > + return scu;
> > +}
> > +EXPORT_SYMBOL_GPL(devm_intel_scu_ipc_dev_get);
> > +
> > /*
> > * Send ipc command
> > * Command Register (Write Only):
> > @@ -167,15 +261,18 @@ static int intel_scu_ipc_check_status(struct intel_scu_ipc_dev *scu)
> > }
> >
> > /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
> > -static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
> > +static int pwr_reg_rdwr(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data,
> > + u32 count, u32 op, u32 id)
> > {
> > - struct intel_scu_ipc_dev *scu = &ipcdev;
> > int nc;
> > u32 offset = 0;
> > int err;
> > u8 cbuf[IPC_WWBUF_SIZE];
> > u32 *wbuf = (u32 *)&cbuf;
> >
> > + if (!scu)
> > + scu = &ipcdev;
> > +
> > memset(cbuf, 0, sizeof(cbuf));
> >
> > mutex_lock(&ipclock);
> > @@ -219,7 +316,8 @@ static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
> > }
> >
> > /**
> > - * intel_scu_ipc_ioread8 - read a word via the SCU
> > + * intel_scu_ipc_dev_ioread8() - Read a byte via the SCU
> > + * @scu: Optional SCU IPC instance
> > * @addr: Register on SCU
> > * @data: Return pointer for read byte
> > *
> > @@ -228,14 +326,15 @@ static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
> > *
> > * This function may sleep.
> > */
> > -int intel_scu_ipc_ioread8(u16 addr, u8 *data)
> > +int intel_scu_ipc_dev_ioread8(struct intel_scu_ipc_dev *scu, u16 addr, u8 *data)
> > {
> > - return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
> > + return pwr_reg_rdwr(scu, &addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_ioread8);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_ioread8);
> >
> > /**
> > - * intel_scu_ipc_iowrite8 - write a byte via the SCU
> > + * intel_scu_ipc_dev_iowrite8() - Write a byte via the SCU
> > + * @scu: Optional SCU IPC instance
> > * @addr: Register on SCU
> > * @data: Byte to write
> > *
> > @@ -244,14 +343,15 @@ EXPORT_SYMBOL(intel_scu_ipc_ioread8);
> > *
> > * This function may sleep.
> > */
> > -int intel_scu_ipc_iowrite8(u16 addr, u8 data)
> > +int intel_scu_ipc_dev_iowrite8(struct intel_scu_ipc_dev *scu, u16 addr, u8 data)
> > {
> > - return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
> > + return pwr_reg_rdwr(scu, &addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_iowrite8);
> >
> > /**
> > - * intel_scu_ipc_readvv - read a set of registers
> > + * intel_scu_ipc_dev_readv() - Read a set of registers
> > + * @scu: Optional SCU IPC instance
> > * @addr: Register list
> > * @data: Bytes to return
> > * @len: Length of array
> > @@ -263,14 +363,16 @@ EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
> > *
> > * This function may sleep.
> > */
> > -int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
> > +int intel_scu_ipc_dev_readv(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data,
> > + size_t len)
> > {
> > - return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
> > + return pwr_reg_rdwr(scu, addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_readv);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_readv);
> >
> > /**
> > - * intel_scu_ipc_writev - write a set of registers
> > + * intel_scu_ipc_dev_writev() - Write a set of registers
> > + * @scu: Optional SCU IPC instance
> > * @addr: Register list
> > * @data: Bytes to write
> > * @len: Length of array
> > @@ -282,14 +384,16 @@ EXPORT_SYMBOL(intel_scu_ipc_readv);
> > *
> > * This function may sleep.
> > */
> > -int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
> > +int intel_scu_ipc_dev_writev(struct intel_scu_ipc_dev *scu, u16 *addr, u8 *data,
> > + size_t len)
> > {
> > - return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
> > + return pwr_reg_rdwr(scu, addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_writev);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_writev);
> >
> > /**
> > - * intel_scu_ipc_update_register - r/m/w a register
> > + * intel_scu_ipc_dev_update() - Update a register
> > + * @scu: Optional SCU IPC instance
> > * @addr: Register address
> > * @bits: Bits to update
> > * @mask: Mask of bits to update
> > @@ -302,15 +406,17 @@ EXPORT_SYMBOL(intel_scu_ipc_writev);
> > * This function may sleep. Locking between SCU accesses is handled
> > * for the caller.
> > */
> > -int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
>
> > +int intel_scu_ipc_dev_update(struct intel_scu_ipc_dev *scu, u16 addr, u8 bits,
> > + u8 mask)
>
> In header you have 'u8 data'. Can we be consistent with a name?
Sure.
> > {
> > u8 data[2] = { bits, mask };
> > - return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
> > + return pwr_reg_rdwr(scu, &addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_update_register);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_update);
> >
> > /**
> > - * intel_scu_ipc_simple_command - send a simple command
> > + * intel_scu_ipc_dev_simple_command() - Send a simple command
> > + * @scu: Optional SCU IPC instance
> > * @cmd: Command
> > * @sub: Sub type
> > *
> > @@ -321,11 +427,14 @@ EXPORT_SYMBOL(intel_scu_ipc_update_register);
> > * This function may sleep. Locking for SCU accesses is handled for the
> > * caller.
> > */
> > -int intel_scu_ipc_simple_command(int cmd, int sub)
> > +int intel_scu_ipc_dev_simple_command(struct intel_scu_ipc_dev *scu, int cmd,
> > + int sub)
> > {
> > - struct intel_scu_ipc_dev *scu = &ipcdev;
> > int err;
> >
> > + if (!scu)
> > + scu = &ipcdev;
> > +
> > mutex_lock(&ipclock);
> > if (scu->dev == NULL) {
> > mutex_unlock(&ipclock);
> > @@ -336,47 +445,65 @@ int intel_scu_ipc_simple_command(int cmd, int sub)
> > mutex_unlock(&ipclock);
> > return err;
> > }
> > -EXPORT_SYMBOL(intel_scu_ipc_simple_command);
> > +EXPORT_SYMBOL(intel_scu_ipc_dev_simple_command);
> >
> > /**
> > - * intel_scu_ipc_command - command with data
> > + * intel_scu_ipc_command_with_size() - Command with data
> > + * @scu: Optional SCU IPC instance
> > * @cmd: Command
> > * @sub: Sub type
> > * @in: Input data
> > - * @inlen: Input length in dwords
> > + * @inlen: Input length in bytes
> > + * @size: Input size written to the IPC command register in whatever
> > + * units (dword, byte) the particular firmware requires. Normally
> > + * should be the same as @inlen.
> > * @out: Output data
> > - * @outlen: Output length in dwords
> > + * @outlen: Output length in bytes
> > *
> > * Issue a command to the SCU which involves data transfers. Do the
> > * data copies under the lock but leave it for the caller to interpret.
> > */
> > -int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
> > - u32 *out, int outlen)
> > +int intel_scu_ipc_dev_command_with_size(struct intel_scu_ipc_dev *scu, int cmd,
> > + int sub, const void *in, size_t inlen,
> > + size_t size, void *out, size_t outlen)
> > {
> > - struct intel_scu_ipc_dev *scu = &ipcdev;
> > + size_t outbuflen = DIV_ROUND_UP(outlen, sizeof(u32));
> > + size_t inbuflen = DIV_ROUND_UP(inlen, sizeof(u32));
> > + u32 inbuf[4] = {};
> > int i, err;
> >
> > + if (inbuflen > 4 || outbuflen > 4)
> > + return -EINVAL;
> > +
> > + if (!scu)
> > + scu = &ipcdev;
> > +
> > mutex_lock(&ipclock);
> > if (scu->dev == NULL) {
> > mutex_unlock(&ipclock);
> > return -ENODEV;
> > }
> >
> > - for (i = 0; i < inlen; i++)
> > - ipc_data_writel(scu, *in++, 4 * i);
> > + memcpy(inbuf, in, inlen);
> > + for (i = 0; i < inbuflen; i++)
> > + ipc_data_writel(scu, inbuf[i], 4 * i);
> >
> > - ipc_command(scu, (inlen << 16) | (sub << 12) | cmd);
> > + ipc_command(scu, (size << 16) | (sub << 12) | cmd);
> > err = intel_scu_ipc_check_status(scu);
> >
> > - if (!err) {
> > - for (i = 0; i < outlen; i++)
> > - *out++ = ipc_data_readl(scu, 4 * i);
>
> > + if (!err && outlen) {
>
> Do we need the 'outlen' test here? In any case if it's zero the following
> will be no-op.
Right, it is not needed. I'll remove the check.
