* [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock
@ 2017-04-26 13:48 Geoff Lansberry
2017-04-26 14:34 ` walter harms
2017-04-26 17:04 ` Mark Greer
0 siblings, 2 replies; 3+ messages in thread
From: Geoff Lansberry @ 2017-04-26 13:48 UTC (permalink / raw)
To: linux-wireless, sameo
Cc: kernel-janitors, linux-kernel, linux-nfc, devicetree, mgreer,
justin, colin.king, Geoff Lansberry
In prior commits the selected clock frequency does not propagate
correctly to what is written the the TRF7970A_MODULATOR_SYS_CLK_CTRL
register.
Also fixes a bug that causes the device tree property check to always
pass.
Signed-off-by: Geoff Lansberry <geoff@kuvee.com>
---
drivers/nfc/trf7970a.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 2d1c8ca..c278b0e 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -2071,7 +2071,7 @@ static int trf7970a_probe(struct spi_device *spi)
}
of_property_read_u32(np, "clock-frequency", &clk_freq);
- if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
+ if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
(clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
dev_err(trf->dev,
"clock-frequency (%u Hz) unsupported\n",
@@ -2079,6 +2079,13 @@ static int trf7970a_probe(struct spi_device *spi)
return -EINVAL;
}
+ if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
+ trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
+ dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
+ } else {
+ trf->modulator_sys_clk_ctrl = 0;
+ }
+
if (of_property_read_bool(np, "en2-rf-quirk"))
trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
--
2.7.4
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock
2017-04-26 13:48 [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock Geoff Lansberry
@ 2017-04-26 14:34 ` walter harms
2017-04-26 17:04 ` Mark Greer
1 sibling, 0 replies; 3+ messages in thread
From: walter harms @ 2017-04-26 14:34 UTC (permalink / raw)
To: Geoff Lansberry
Cc: linux-wireless, sameo, kernel-janitors, linux-kernel, linux-nfc,
devicetree, mgreer, justin, colin.king
Am 26.04.2017 15:48, schrieb Geoff Lansberry:
> In prior commits the selected clock frequency does not propagate
> correctly to what is written the the TRF7970A_MODULATOR_SYS_CLK_CTRL
> register.
> Also fixes a bug that causes the device tree property check to always
> pass.
>
> Signed-off-by: Geoff Lansberry <geoff@kuvee.com>
> ---
> drivers/nfc/trf7970a.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
> index 2d1c8ca..c278b0e 100644
> --- a/drivers/nfc/trf7970a.c
> +++ b/drivers/nfc/trf7970a.c
> @@ -2071,7 +2071,7 @@ static int trf7970a_probe(struct spi_device *spi)
> }
>
> of_property_read_u32(np, "clock-frequency", &clk_freq);
> - if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
> + if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
> (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
> dev_err(trf->dev,
> "clock-frequency (%u Hz) unsupported\n",
> @@ -2079,6 +2079,13 @@ static int trf7970a_probe(struct spi_device *spi)
> return -EINVAL;
> }
>
> + if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
> + trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
> + dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
> + } else {
> + trf->modulator_sys_clk_ctrl = 0;
> + }
> +
I am a fan of defensive programming and would move do:
trf->modulator_sys_clk_ctrl = 0;
if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
}
perhaps using a switch/case here is appropriate IMHO a border case for 2 case
but would make the init code more clear.
just my 2 cents,
re,
wh
> if (of_property_read_bool(np, "en2-rf-quirk"))
> trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock
2017-04-26 13:48 [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock Geoff Lansberry
2017-04-26 14:34 ` walter harms
@ 2017-04-26 17:04 ` Mark Greer
1 sibling, 0 replies; 3+ messages in thread
From: Mark Greer @ 2017-04-26 17:04 UTC (permalink / raw)
To: Geoff Lansberry, g
Cc: linux-wireless, sameo, kernel-janitors, linux-kernel, linux-nfc,
devicetree, mgreer, justin, colin.king
On Wed, Apr 26, 2017 at 09:48:33AM -0400, Geoff Lansberry wrote:
> In prior commits the selected clock frequency does not propagate
> correctly to what is written the the TRF7970A_MODULATOR_SYS_CLK_CTRL
> register.
> Also fixes a bug that causes the device tree property check to always
> pass.
>
> Signed-off-by: Geoff Lansberry <geoff@kuvee.com>
> ---
> drivers/nfc/trf7970a.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
> index 2d1c8ca..c278b0e 100644
> --- a/drivers/nfc/trf7970a.c
> +++ b/drivers/nfc/trf7970a.c
> @@ -2071,7 +2071,7 @@ static int trf7970a_probe(struct spi_device *spi)
> }
>
> of_property_read_u32(np, "clock-frequency", &clk_freq);
> - if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
> + if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
There is already a patch submitted to fix this issue so no need to fix
it again. For the record, it should have been in a separate patch
since it fixes a different issue than what is fixed below.
> (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
> dev_err(trf->dev,
> "clock-frequency (%u Hz) unsupported\n",
> @@ -2079,6 +2079,13 @@ static int trf7970a_probe(struct spi_device *spi)
> return -EINVAL;
> }
>
> + if (clk_freq == TRF7970A_27MHZ_CLOCK_FREQUENCY) {
> + trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
> + dev_dbg(trf->dev, "trf7970a configured for 27MHz crystal\n");
> + } else {
> + trf->modulator_sys_clk_ctrl = 0;
> + }
> +
> if (of_property_read_bool(np, "en2-rf-quirk"))
> trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
This part looks okay to me but I like Walter's suggestion too.
Mark
--
^ permalink raw reply [flat|nested] 3+ messages in thread
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2017-04-26 13:48 [PATCH] NFC: trf7970a: Correct register settings for 27MHz clock Geoff Lansberry
2017-04-26 14:34 ` walter harms
2017-04-26 17:04 ` Mark Greer
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