| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20200503211037.eovuhtugmg2vy4er@earth.universe>
Date: Sun, 3 May 2020 23:10:37 +0200
From: Sebastian Reichel <sebastian.reichel@...labora.com>
To: Michał Mirosław <mirq-linux@...e.qmqm.pl>
Cc: Rob Herring <robh+dt@...nel.org>, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org
Subject: Re: [PATCH v2 04/11] power: bq25890: protect view of the chip's state
Hi,
On Sun, May 03, 2020 at 05:21:11PM +0200, Michał Mirosław wrote:
> Extend bq->lock over whole updating of the chip's state. Might get
> useful later for switching ADC modes correctly.
>
> Signed-off-by: Michał Mirosław <mirq-linux@...e.qmqm.pl>
> ---
Thanks, queued.
-- Sebastian
> drivers/power/supply/bq25890_charger.c | 82 ++++++++------------------
> 1 file changed, 26 insertions(+), 56 deletions(-)
>
> diff --git a/drivers/power/supply/bq25890_charger.c b/drivers/power/supply/bq25890_charger.c
> index c4a69fd69f34..9339e216651f 100644
> --- a/drivers/power/supply/bq25890_charger.c
> +++ b/drivers/power/supply/bq25890_charger.c
> @@ -510,74 +510,50 @@ static int bq25890_get_chip_state(struct bq25890_device *bq,
> return 0;
> }
>
> -static bool bq25890_state_changed(struct bq25890_device *bq,
> - struct bq25890_state *new_state)
> -{
> - struct bq25890_state old_state;
> -
> - mutex_lock(&bq->lock);
> - old_state = bq->state;
> - mutex_unlock(&bq->lock);
> -
> - return (old_state.chrg_status != new_state->chrg_status ||
> - old_state.chrg_fault != new_state->chrg_fault ||
> - old_state.online != new_state->online ||
> - old_state.bat_fault != new_state->bat_fault ||
> - old_state.boost_fault != new_state->boost_fault ||
> - old_state.vsys_status != new_state->vsys_status);
> -}
> -
> -static void bq25890_handle_state_change(struct bq25890_device *bq,
> - struct bq25890_state *new_state)
> +static irqreturn_t __bq25890_handle_irq(struct bq25890_device *bq)
> {
> + struct bq25890_state new_state;
> int ret;
> - struct bq25890_state old_state;
>
> - mutex_lock(&bq->lock);
> - old_state = bq->state;
> - mutex_unlock(&bq->lock);
> + ret = bq25890_get_chip_state(bq, &new_state);
> + if (ret < 0)
> + return IRQ_NONE;
>
> - if (!new_state->online) { /* power removed */
> + if (!memcmp(&bq->state, &new_state, sizeof(new_state)))
> + return IRQ_NONE;
> +
> + if (!new_state.online && bq->state.online) { /* power removed */
> /* disable ADC */
> ret = bq25890_field_write(bq, F_CONV_START, 0);
> if (ret < 0)
> goto error;
> - } else if (!old_state.online) { /* power inserted */
> + } else if (new_state.online && !bq->state.online) { /* power inserted */
> /* enable ADC, to have control of charge current/voltage */
> ret = bq25890_field_write(bq, F_CONV_START, 1);
> if (ret < 0)
> goto error;
> }
>
> - return;
> + bq->state = new_state;
> + power_supply_changed(bq->charger);
>
> + return IRQ_HANDLED;
> error:
> - dev_err(bq->dev, "Error communicating with the chip.\n");
> + dev_err(bq->dev, "Error communicating with the chip: %pe\n",
> + ERR_PTR(ret));
> + return IRQ_HANDLED;
> }
>
> static irqreturn_t bq25890_irq_handler_thread(int irq, void *private)
> {
> struct bq25890_device *bq = private;
> - int ret;
> - struct bq25890_state state;
> -
> - ret = bq25890_get_chip_state(bq, &state);
> - if (ret < 0)
> - goto handled;
> -
> - if (!bq25890_state_changed(bq, &state))
> - goto handled;
> -
> - bq25890_handle_state_change(bq, &state);
> + irqreturn_t ret;
>
> mutex_lock(&bq->lock);
> - bq->state = state;
> + ret = __bq25890_handle_irq(bq);
> mutex_unlock(&bq->lock);
>
> - power_supply_changed(bq->charger);
> -
> -handled:
> - return IRQ_HANDLED;
> + return ret;
> }
>
> static int bq25890_chip_reset(struct bq25890_device *bq)
> @@ -607,7 +583,6 @@ static int bq25890_hw_init(struct bq25890_device *bq)
> {
> int ret;
> int i;
> - struct bq25890_state state;
>
> const struct {
> enum bq25890_fields id;
> @@ -655,16 +630,12 @@ static int bq25890_hw_init(struct bq25890_device *bq)
> return ret;
> }
>
> - ret = bq25890_get_chip_state(bq, &state);
> + ret = bq25890_get_chip_state(bq, &bq->state);
> if (ret < 0) {
> dev_dbg(bq->dev, "Get state failed %d\n", ret);
> return ret;
> }
>
> - mutex_lock(&bq->lock);
> - bq->state = state;
> - mutex_unlock(&bq->lock);
> -
> return 0;
> }
>
> @@ -1001,19 +972,16 @@ static int bq25890_suspend(struct device *dev)
> static int bq25890_resume(struct device *dev)
> {
> int ret;
> - struct bq25890_state state;
> struct bq25890_device *bq = dev_get_drvdata(dev);
>
> - ret = bq25890_get_chip_state(bq, &state);
> + mutex_lock(&bq->lock);
> +
> + ret = bq25890_get_chip_state(bq, &bq->state);
> if (ret < 0)
> return ret;
>
> - mutex_lock(&bq->lock);
> - bq->state = state;
> - mutex_unlock(&bq->lock);
> -
> /* Re-enable ADC only if charger is plugged in. */
> - if (state.online) {
> + if (bq->state.online) {
> ret = bq25890_field_write(bq, F_CONV_START, 1);
> if (ret < 0)
> return ret;
> @@ -1022,6 +990,8 @@ static int bq25890_resume(struct device *dev)
> /* signal userspace, maybe state changed while suspended */
> power_supply_changed(bq->charger);
>
> + mutex_unlock(&bq->lock);
> +
> return 0;
> }
> #endif
> --
> 2.20.1
>
Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)
Powered by blists - more mailing lists