Re: [PATCH v4 06/12] [media] cxd2880: Add integration layer for the driver

From: Sean Young
Date: Sun Dec 03 2017 - 13:23:55 EST


On Fri, Oct 13, 2017 at 03:08:34PM +0900, Yasunari.Takiguchi@xxxxxxxx wrote:
> From: Yasunari Takiguchi <Yasunari.Takiguchi@xxxxxxxx>
>
> These functions monitor the driver and watch for task completion.
> This is part of the Sony CXD2880 DVB-T2/T tuner + demodulator driver.
>
> Signed-off-by: Yasunari Takiguchi <Yasunari.Takiguchi@xxxxxxxx>
> Signed-off-by: Masayuki Yamamoto <Masayuki.Yamamoto@xxxxxxxx>
> Signed-off-by: Hideki Nozawa <Hideki.Nozawa@xxxxxxxx>
> Signed-off-by: Kota Yonezawa <Kota.Yonezawa@xxxxxxxx>
> Signed-off-by: Toshihiko Matsumoto <Toshihiko.Matsumoto@xxxxxxxx>
> Signed-off-by: Satoshi Watanabe <Satoshi.C.Watanabe@xxxxxxxx>
> ---
>
> [Change list]
> Changes in V4
> drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c
> -removed unnecessary initialization at variable declaration
>
> Changes in V3
> drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c
> -changed cxd2880_atomic_read to atomic_read
> -changed cxd2880_atomic_set to atomic_set
> -modified return code
> -modified coding style of if()
> drivers/media/dvb-frontends/cxd2880/cxd2880_integ.h
> -modified return code
>
> .../media/dvb-frontends/cxd2880/cxd2880_integ.c | 98 ++++++++++++++++++++++
> .../media/dvb-frontends/cxd2880/cxd2880_integ.h | 44 ++++++++++
> 2 files changed, 142 insertions(+)
> create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c
> create mode 100644 drivers/media/dvb-frontends/cxd2880/cxd2880_integ.h
>
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c b/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c
> new file mode 100644
> index 000000000000..7264fc355d6b
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.c
> @@ -0,0 +1,98 @@
> +/*
> + * cxd2880_integ.c
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * integration layer 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_tnrdmd.h"
> +#include "cxd2880_tnrdmd_mon.h"
> +#include "cxd2880_integ.h"
> +
> +int cxd2880_integ_init(struct cxd2880_tnrdmd *tnr_dmd)
> +{
> + int ret;
> + struct cxd2880_stopwatch timer;
> + unsigned int elapsed_time = 0;
> + u8 cpu_task_completed = 0;
> +
> + if (!tnr_dmd)
> + return -EINVAL;
> +
> + ret = cxd2880_tnrdmd_init1(tnr_dmd);
> + if (ret)
> + return ret;
> +
> + ret = cxd2880_stopwatch_start(&timer);
> + if (ret)
> + return ret;
> +
> + while (1) {
> + ret = cxd2880_stopwatch_elapsed(&timer, &elapsed_time);
> + if (ret)
> + return ret;
> +
> + ret =
> + cxd2880_tnrdmd_check_internal_cpu_status(tnr_dmd,
> + &cpu_task_completed);
> + if (ret)
> + return ret;
> +
> + if (cpu_task_completed)
> + break;
> +
> + if (elapsed_time > CXD2880_TNRDMD_WAIT_INIT_TIMEOUT)
> + return -ETIME;

ETIMEOUT?

> + ret =
> + cxd2880_stopwatch_sleep(&timer,
> + CXD2880_TNRDMD_WAIT_INIT_INTVL);
> + if (ret)
> + return ret;
> + }

This could be simplified. Also, I'm worried that the jiffies code in
cxd2880_stopwatch_port.c does not deal with jiffies wrapping correctly; working
with ktime easier in that regard.

{
ktime_t start = ktime_get();

for (;;) {
ret = check_status(&task_completed);
if (ret)
return ret;

if (task_completed)
break;

if (ktime_to_ms(ktime_sub(ktime_get(), start)) >
CXD2880_TNRDMD_WAIT_INIT_TIMEOUT)
return -ETIMEDOUT;

usleep_range(CXD2880_TNRDMD_WAIT_INIT_INTVL,
CXD2880_TNRDMD_WAIT_INIT_INTVL + 1000);
}
}

This removes the need for the cxd2880_stopwatch_* functions.
> +
> + ret = cxd2880_tnrdmd_init2(tnr_dmd);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +int cxd2880_integ_cancel(struct cxd2880_tnrdmd *tnr_dmd)
> +{
> + if (!tnr_dmd)
> + return -EINVAL;
> +
> + atomic_set(&tnr_dmd->cancel, 1);
> +
> + return 0;
> +}
> +
> +int cxd2880_integ_check_cancellation(struct cxd2880_tnrdmd *tnr_dmd)
> +{
> + if (!tnr_dmd)
> + return -EINVAL;
> +
> + if (atomic_read(&tnr_dmd->cancel) != 0)
> + return -ECANCELED;
> +
> + return 0;
> +}
> diff --git a/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.h b/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.h
> new file mode 100644
> index 000000000000..2b4fe5c3743b
> --- /dev/null
> +++ b/drivers/media/dvb-frontends/cxd2880/cxd2880_integ.h
> @@ -0,0 +1,44 @@
> +/*
> + * cxd2880_integ.h
> + * Sony CXD2880 DVB-T2/T tuner + demodulator driver
> + * integration layer common interface
> + *
> + * 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_INTEG_H
> +#define CXD2880_INTEG_H
> +
> +#include "cxd2880_tnrdmd.h"
> +
> +#define CXD2880_TNRDMD_WAIT_INIT_TIMEOUT 500
> +#define CXD2880_TNRDMD_WAIT_INIT_INTVL 10
> +
> +#define CXD2880_TNRDMD_WAIT_AGC_STABLE 100
> +
> +int cxd2880_integ_init(struct cxd2880_tnrdmd *tnr_dmd);
> +
> +int cxd2880_integ_cancel(struct cxd2880_tnrdmd *tnr_dmd);
> +
> +int cxd2880_integ_check_cancellation(struct cxd2880_tnrdmd
> + *tnr_dmd);
> +
> +#endif
> --
> 2.13.0