2023-12-19 17:20:34

by Hugo Villeneuve

Subject: [PATCH 15/18] serial: sc16is7xx: pass R/W buffer in FIFO functions

From: Hugo Villeneuve <[email protected]>

To simplify function by avoiding cast.

This is similar to what is done in max310x driver.

Signed-off-by: Hugo Villeneuve <[email protected]>
---
If deemed appropriate for stable kernel backporting:
Fixes: dec273ecc116 ("sc16is7xx: fix FIFO address of secondary UART")
Cc: [email protected]
---
drivers/tty/serial/sc16is7xx.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index a9e44e5ef713..3322507ab18e 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -380,17 +380,15 @@ static void sc16is7xx_port_write(struct uart_port *port, u8 reg, u8 val)
regmap_write(one->regmap, reg, val);
}

-static void sc16is7xx_fifo_read(struct uart_port *port, unsigned int rxlen)
+static void sc16is7xx_fifo_read(struct uart_port *port, u8 *rxbuf, unsigned int rxlen)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);

- regmap_noinc_read(one->regmap, SC16IS7XX_RHR_REG, s->buf, rxlen);
+ regmap_noinc_read(one->regmap, SC16IS7XX_RHR_REG, rxbuf, rxlen);
}

-static void sc16is7xx_fifo_write(struct uart_port *port, u8 to_send)
+static void sc16is7xx_fifo_write(struct uart_port *port, u8 *txbuf, u8 to_send)
{
- struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);

/*
@@ -400,7 +398,7 @@ static void sc16is7xx_fifo_write(struct uart_port *port, u8 to_send)
if (unlikely(!to_send))
return;

- regmap_noinc_write(one->regmap, SC16IS7XX_THR_REG, s->buf, to_send);
+ regmap_noinc_write(one->regmap, SC16IS7XX_THR_REG, txbuf, to_send);
}

static void sc16is7xx_port_update(struct uart_port *port, u8 reg,
@@ -576,7 +574,7 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
s->buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
bytes_read = 1;
} else {
- sc16is7xx_fifo_read(port, rxlen);
+ sc16is7xx_fifo_read(port, s->buf, rxlen);
bytes_read = rxlen;
}

@@ -665,7 +663,7 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
uart_xmit_advance(port, 1);
}

- sc16is7xx_fifo_write(port, to_send);
+ sc16is7xx_fifo_write(port, s->buf, to_send);
}

uart_port_lock_irqsave(port, &flags);
--
2.39.2

2023-12-20 16:04:36

by Andy Shevchenko

Subject: Re: [PATCH 15/18] serial: sc16is7xx: pass R/W buffer in FIFO functions

On Tue, Dec 19, 2023 at 12:18:59PM -0500, Hugo Villeneuve wrote:
> From: Hugo Villeneuve <[email protected]>
>
> To simplify function by avoiding cast.
>
> This is similar to what is done in max310x driver.

...

> ---
> If deemed appropriate for stable kernel backporting:

I don't think it's eligible.

> ---

I don't see the necessity of the change, OTOH it's harmless.
The problem is that commit message is basically "Yeah, we
do cargo cult." Because I haven't seen what casting you are
talking about.

--
With Best Regards,
Andy Shevchenko

2023-12-21 19:36:29

by Hugo Villeneuve

Subject: Re: [PATCH 15/18] serial: sc16is7xx: pass R/W buffer in FIFO functions

On Wed, 20 Dec 2023 17:57:59 +0200
Andy Shevchenko <[email protected]> wrote:

> On Tue, Dec 19, 2023 at 12:18:59PM -0500, Hugo Villeneuve wrote:
> > From: Hugo Villeneuve <[email protected]>
> >
> > To simplify function by avoiding cast.
> >
> > This is similar to what is done in max310x driver.
>
> ...
>
> > ---
> > If deemed appropriate for stable kernel backporting:
>
> I don't think it's eligible.

No problem.


> > ---
>
> I don't see the necessity of the change, OTOH it's harmless.
> The problem is that commit message is basically "Yeah, we
> do cargo cult." Because I haven't seen what casting you are
> talking about.

I'll try to reword the commit message.

And replace cast with something like "... to remove additional struct
sc16is7xx_port variable..."

Hugo Villeneuve