Message-ID: <20170613091301.3c8e63a9@vento.lan>
Date:   Tue, 13 Jun 2017 09:13:01 -0300
From:   Mauro Carvalho Chehab <mchehab@...pensource.com>
To:     <Yasunari.Takiguchi@...y.com>
Cc:     <linux-kernel@...r.kernel.org>, <devicetree@...r.kernel.org>,
        <linux-media@...r.kernel.org>, <tbird20d@...il.com>,
        <frowand.list@...il.com>,
        Masayuki Yamamoto <Masayuki.Yamamoto@...y.com>,
        Hideki Nozawa <Hideki.Nozawa@...y.com>,
        "Kota Yonezawa" <Kota.Yonezawa@...y.com>,
        Toshihiko Matsumoto <Toshihiko.Matsumoto@...y.com>,
        Satoshi Watanabe <Satoshi.C.Watanabe@...y.com>
Subject: Re: [PATCH v2 03/15] [media] cxd2880: Add common files for the
 driver

Em Fri, 14 Apr 2017 11:17:01 +0900
<Yasunari.Takiguchi@...y.com> escreveu:

> From: Yasunari Takiguchi <Yasunari.Takiguchi@...y.com>
> 
> These are common files for the driver for the
> Sony CXD2880 DVB-T2/T tuner + demodulator.
> These contains helper functions for the driver.
> 
> Signed-off-by: Yasunari Takiguchi <Yasunari.Takiguchi@...y.com>
> Signed-off-by: Masayuki Yamamoto <Masayuki.Yamamoto@...y.com>
> Signed-off-by: Hideki Nozawa <Hideki.Nozawa@...y.com>
> Signed-off-by: Kota Yonezawa <Kota.Yonezawa@...y.com>
> Signed-off-by: Toshihiko Matsumoto <Toshihiko.Matsumoto@...y.com>
> Signed-off-by: Satoshi Watanabe <Satoshi.C.Watanabe@...y.com>
> ---
>  drivers/media/dvb-frontends/cxd2880/cxd2880.h      | 46 ++++++++++++
>  .../media/dvb-frontends/cxd2880/cxd2880_common.c   | 84 +++++++++++++++++++++
>  .../media/dvb-frontends/cxd2880/cxd2880_common.h   | 86 ++++++++++++++++++++++
>  drivers/media/dvb-frontends/cxd2880/cxd2880_io.c   | 68 +++++++++++++++++
>  drivers/media/dvb-frontends/cxd2880/cxd2880_io.h   | 62 ++++++++++++++++
>  .../media/dvb-frontends/cxd2880/cxd2880_stdlib.h   | 35 +++++++++
>  .../dvb-frontends/cxd2880/cxd2880_stopwatch_port.c | 71 ++++++++++++++++++
>  7 files changed, 452 insertions(+)
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880.h
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_common.c
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_common.h
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_io.c
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_io.h
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_stdlib.h
>  create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_stopwatch_port.c
> 
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880.h b/drivers/media/dvb-frontends/cxd2880/cxd2880.h
> new file mode 100644
> index 000000000000..281f9a784eb5
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880.h
> @@ -0,0 +1,46 @@
> +/*
> + * cxd2880.h
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver public definitions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef CXD2880_H
> +#define CXD2880_H
> +
> +struct cxd2880_config {
> +	struct spi_device *spi;
> +	struct mutex *spi_mutex; /* For SPI access exclusive control */
> +};
> +
> +#if IS_REACHABLE(CONFIG_DVB_CXD2880)
> +extern struct dvb_frontend *cxd2880_attach(struct dvb_frontend *fe,
> +					struct cxd2880_config *cfg);
> +#else
> +static inline struct dvb_frontend *cxd2880_attach(struct dvb_frontend *fe,
> +					struct cxd2880_config *cfg)
> +{
> +	pr_warn("%s: driver disabled by Kconfig\n", __func__);
> +	return NULL;
> +}
> +#endif /* CONFIG_DVB_CXD2880 */
> +
> +#endif /* CXD2880_H */
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_common.c b/drivers/media/dvb-frontends/cxd2880/cxd2880_common.c
> new file mode 100644
> index 000000000000..850f3a76b2c7
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_common.c
> @@ -0,0 +1,84 @@
> +/*
> + * cxd2880_common.c
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * common functions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include "cxd2880_common.h"
> +
> +#define MASKUPPER(n) (((n) == 0) ? 0 : (0xFFFFFFFFU << (32 - (n))))
> +#define MASKLOWER(n) (((n) == 0) ? 0 : (0xFFFFFFFFU >> (32 - (n))))

Please prefer using the already existing bit macros at:
	include/linux/bitfield.h
	include/linux/bitops.h

> +
> +int cxd2880_convert2s_complement(u32 value, u32 bitlen)
> +{
> +	if ((bitlen == 0) || (bitlen >= 32))
> +		return (int)value;
> +
> +	if (value & (u32)(1 << (bitlen - 1)))
> +		return (int)(MASKUPPER(32 - bitlen) | value);
> +	else
> +		return (int)(MASKLOWER(bitlen) & value);
> +}
> +
> +u32 cxd2880_bit_split_from_byte_array(u8 *array, u32 start_bit, u32 bit_num)
> +{
> +	u32 value = 0;
> +	u8 *array_read;
> +	u8 bit_read;
> +	u32 len_remain;
> +
> +	if (!array)
> +		return 0;
> +	if ((bit_num == 0) || (bit_num > 32))
> +		return 0;
> +
> +	array_read = array + (start_bit / 8);
> +	bit_read = (u8)(start_bit % 8);
> +	len_remain = bit_num;
> +
> +	if (bit_read != 0) {
> +		if (((int)len_remain) <= 8 - bit_read) {
> +			value = (*array_read) >> ((8 - bit_read) - len_remain);
> +			len_remain = 0;
> +		} else {
> +			value = *array_read++;
> +			len_remain -= 8 - bit_read;
> +		}
> +	}
> +
> +	while (len_remain > 0) {
> +		if (len_remain < 8) {
> +			value <<= len_remain;
> +			value |= (*array_read++ >> (8 - len_remain));
> +			len_remain = 0;
> +		} else {
> +			value <<= 8;
> +			value |= (u32)(*array_read++);
> +			len_remain -= 8;
> +		}
> +	}
> +
> +	value &= MASKLOWER(bit_num);
> +
> +	return value;
> +}

The Kernel has already optimized macros to handle with bit arrays.

I suspect that you could get what you're doing above with this
macro (defined at include/linux/bitops.h):
	for_each_set_bit()

The Kernel macros usually take advantage of some machine instructions
to find bits, if available at the specific architecture the driver is
compiled.

> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_common.h b/drivers/media/dvb-frontends/cxd2880/cxd2880_common.h
> new file mode 100644
> index 000000000000..b1ecb44bca10
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_common.h
> @@ -0,0 +1,86 @@
> +/*
> + * cxd2880_common.h
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver common definitions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef CXD2880_COMMON_H
> +#define CXD2880_COMMON_H
> +
> +#include <linux/types.h>
> +
> +#ifndef NULL
> +#ifdef __cplusplus
> +#define NULL 0
> +#else
> +#define NULL ((void *)0)
> +#endif
> +#endif

Please remove the above. NULL is already defined, and we don't compile the
Kernel on c++.

> +
> +#include <linux/delay.h>

> +#define CXD2880_SLEEP(n) msleep(n)
> +#ifndef CXD2880_SLEEP_IN_MON
> +#define CXD2880_SLEEP_IN_MON(n, obj) CXD2880_SLEEP(n)
> +#endif
> +
> +#define CXD2880_ARG_UNUSED(arg) ((void)(arg))

Please get rid of the above too, as the above just obfuscates the
code.

> +
> +enum cxd2880_ret {
> +	CXD2880_RESULT_OK,
> +	CXD2880_RESULT_ERROR_ARG,
> +	CXD2880_RESULT_ERROR_IO,
> +	CXD2880_RESULT_ERROR_SW_STATE,
> +	CXD2880_RESULT_ERROR_HW_STATE,
> +	CXD2880_RESULT_ERROR_TIMEOUT,
> +	CXD2880_RESULT_ERROR_UNLOCK,
> +	CXD2880_RESULT_ERROR_RANGE,
> +	CXD2880_RESULT_ERROR_NOSUPPORT,
> +	CXD2880_RESULT_ERROR_CANCEL,
> +	CXD2880_RESULT_ERROR_OTHER,
> +	CXD2880_RESULT_ERROR_OVERFLOW,
> +	CXD2880_RESULT_OK_CONFIRM
> +};

Please don't define your own return codes. Use the Posix-based error
codes, e. g.:

0 for OK
-EINVAL
-EOVERFLOW
...


> +
> +int cxd2880_convert2s_complement(u32 value, u32 bitlen);
> +
> +u32 cxd2880_bit_split_from_byte_array(u8 *array, u32 start_bit, u32 bit_num);
> +
> +struct cxd2880_atomic {
> +	int counter;
> +};
> +
> +#define cxd2880_atomic_set(a, i) ((a)->counter = i)
> +#define cxd2880_atomic_read(a) ((a)->counter)

No. Use the macros at include/linux/atomic.h for atomic operations.

> +
> +struct cxd2880_stopwatch {
> +	u32 start_time;
> +};
> +
> +enum cxd2880_ret cxd2880_stopwatch_start(struct cxd2880_stopwatch *stopwatch);
> +
> +enum cxd2880_ret cxd2880_stopwatch_sleep(struct cxd2880_stopwatch *stopwatch,
> +					 u32 ms);
> +
> +enum cxd2880_ret cxd2880_stopwatch_elapsed(struct cxd2880_stopwatch *stopwatch,
> +					   u32 *elapsed);
> +
> +#endif
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_io.c b/drivers/media/dvb-frontends/cxd2880/cxd2880_io.c
> new file mode 100644
> index 000000000000..f0f82055a953
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_io.c
> @@ -0,0 +1,68 @@
> +/*
> + * cxd2880_io.c
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * register I/O interface functions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include "cxd2880_io.h"
> +
> +enum cxd2880_ret cxd2880_io_common_write_one_reg(struct cxd2880_io *io,
> +						 enum cxd2880_io_tgt tgt,
> +						 u8 sub_address, u8 data)
> +{
> +	enum cxd2880_ret ret = CXD2880_RESULT_OK;
> +
> +	if (!io)
> +		return CXD2880_RESULT_ERROR_ARG;
> +
> +	ret = io->write_regs(io, tgt, sub_address, &data, 1);
> +
> +	return ret;
> +}

Here (and below): use the standard linux error codes.

> +
> +enum cxd2880_ret cxd2880_io_set_reg_bits(struct cxd2880_io *io,
> +					 enum cxd2880_io_tgt tgt,
> +					 u8 sub_address, u8 data, u8 mask)
> +{
> +	enum cxd2880_ret ret = CXD2880_RESULT_OK;
> +
> +	if (!io)
> +		return CXD2880_RESULT_ERROR_ARG;
> +
> +	if (mask == 0x00)
> +		return CXD2880_RESULT_OK;
> +
> +	if (mask != 0xFF) {

nitpick: we usually prefer hex numbers in low cases. In any case, please
be coherent along the driver.

> +		u8 rdata = 0x00;
> +
> +		ret = io->read_regs(io, tgt, sub_address, &rdata, 1);
> +		if (ret != CXD2880_RESULT_OK)
> +			return ret;
> +
> +		data = (u8)((data & mask) | (rdata & (mask ^ 0xFF)));
> +	}
> +
> +	ret = io->write_reg(io, tgt, sub_address, data);
> +
> +	return ret;
> +}
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_io.h b/drivers/media/dvb-frontends/cxd2880/cxd2880_io.h
> new file mode 100644
> index 000000000000..4d6db13cf910
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_io.h
> @@ -0,0 +1,62 @@
> +/*
> + * cxd2880_io.h
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * register I/O interface definitions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef CXD2880_IO_H
> +#define CXD2880_IO_H
> +
> +#include "cxd2880_common.h"
> +
> +enum cxd2880_io_tgt {
> +	CXD2880_IO_TGT_SYS,
> +	CXD2880_IO_TGT_DMD
> +};
> +
> +struct cxd2880_io {
> +	enum cxd2880_ret (*read_regs)(struct cxd2880_io *io,
> +				       enum cxd2880_io_tgt tgt, u8 sub_address,
> +				       u8 *data, u32 size);
> +	enum cxd2880_ret (*write_regs)(struct cxd2880_io *io,
> +					enum cxd2880_io_tgt tgt, u8 sub_address,
> +					const u8 *data, u32 size);
> +	enum cxd2880_ret (*write_reg)(struct cxd2880_io *io,
> +				       enum cxd2880_io_tgt tgt, u8 sub_address,
> +				       u8 data);
> +	void *if_object;
> +	u8 i2c_address_sys;
> +	u8 i2c_address_demod;
> +	u8 slave_select;
> +	void *user;
> +};
> +
> +enum cxd2880_ret cxd2880_io_common_write_one_reg(struct cxd2880_io *io,
> +						 enum cxd2880_io_tgt tgt,
> +						 u8 sub_address, u8 data);
> +
> +enum cxd2880_ret cxd2880_io_set_reg_bits(struct cxd2880_io *io,
> +					 enum cxd2880_io_tgt tgt,
> +					 u8 sub_address, u8 data, u8 mask);
> +
> +#endif
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_stdlib.h b/drivers/media/dvb-frontends/cxd2880/cxd2880_stdlib.h
> new file mode 100644
> index 000000000000..b9ca1b9df110
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_stdlib.h
> @@ -0,0 +1,35 @@
> +/*
> + * cxd2880_stdlib.h
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * standard lib function aliases
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef CXD2880_STDLIB_H
> +#define CXD2880_STDLIB_H
> +
> +#include <linux/string.h>
> +
> +#define cxd2880_memcpy  memcpy
> +#define cxd2880_memset  memset

No. Just use memcpy()/memset() and get rid of this header.

> +
> +#endif
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_stopwatch_port.c b/drivers/media/dvb-frontends/cxd2880/cxd2880_stopwatch_port.c
> new file mode 100644
> index 000000000000..14ad6aa6c4c0
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_stopwatch_port.c
> @@ -0,0 +1,71 @@
> +/*
> + * cxd2880_stopwatch_port.c
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * time measurement functions
> + *
> + * Copyright (C) 2016, 2017 Sony Semiconductor Solutions Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; version 2 of the License.
> + *
> + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
> + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
> + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
> + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
> + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
> + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
> + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include "cxd2880_common.h"
> +
> +#include <linux/ktime.h>
> +#include <linux/time.h>
> +#include <linux/timekeeping.h>
> +
> +static u32 get_time_count(void)
> +{
> +	struct timespec tp;
> +
> +	getnstimeofday(&tp);

As said before, don't use it for timeout checks.

> +
> +	return (u32)((tp.tv_sec * 1000) + (tp.tv_nsec / 1000000));
> +}
> +
> +enum cxd2880_ret cxd2880_stopwatch_start(struct cxd2880_stopwatch *stopwatch)
> +{
> +	if (!stopwatch)
> +		return CXD2880_RESULT_ERROR_ARG;
> +
> +	stopwatch->start_time = get_time_count();
> +
> +	return CXD2880_RESULT_OK;
> +}
> +
> +enum cxd2880_ret cxd2880_stopwatch_sleep(struct cxd2880_stopwatch *stopwatch,
> +					 u32 ms)
> +{
> +	if (!stopwatch)
> +		return CXD2880_RESULT_ERROR_ARG;
> +	CXD2880_ARG_UNUSED(*stopwatch);
> +	CXD2880_SLEEP(ms);
> +
> +	return CXD2880_RESULT_OK;
> +}
> +
> +enum cxd2880_ret cxd2880_stopwatch_elapsed(struct cxd2880_stopwatch *stopwatch,
> +					   u32 *elapsed)
> +{
> +	if (!stopwatch || !elapsed)
> +		return CXD2880_RESULT_ERROR_ARG;
> +	*elapsed = get_time_count() - stopwatch->start_time;
> +
> +	return CXD2880_RESULT_OK;
> +}

You should reimplement the above using jiffies.

Thanks,
Mauro

Powered by blists - more mailing lists