diff mbox

[1/3] NFC: trf7970a: add device tree option for 27MHz clock

Message ID 1482250592-4268-1-git-send-email-glansberry@gmail.com (mailing list archive)
State Superseded
Delegated to: Samuel Ortiz
Headers show

Commit Message

Geoff Lansberry Dec. 20, 2016, 4:16 p.m. UTC
From: Geoff Lansberry <geoff@kuvee.com>

The TRF7970A has configuration options to support hardware designs
which use a 27.12MHz clock. This commit adds a device tree option
'clock-frequency' to support configuring the this chip for default
13.56MHz clock or the optional 27.12MHz clock.
---
 .../devicetree/bindings/net/nfc/trf7970a.txt       |  4 ++
 drivers/nfc/trf7970a.c                             | 50 +++++++++++++++++-----
 2 files changed, 43 insertions(+), 11 deletions(-)

Comments

Jones Desougi Dec. 20, 2016, 5:58 p.m. UTC | #1
On 2016-12-20 17:16, Geoff Lansberry wrote:
> From: Geoff Lansberry <geoff@kuvee.com>
> 
> The TRF7970A has configuration options to support hardware designs
> which use a 27.12MHz clock. This commit adds a device tree option
> 'clock-frequency' to support configuring the this chip for default
> 13.56MHz clock or the optional 27.12MHz clock.
> ---
>  .../devicetree/bindings/net/nfc/trf7970a.txt       |  4 ++
>  drivers/nfc/trf7970a.c                             | 50 +++++++++++++++++-----
>  2 files changed, 43 insertions(+), 11 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> index 32b35a0..e262ac1 100644
> --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> @@ -21,6 +21,8 @@ Optional SoC Specific Properties:
>  - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum
>    where an extra byte is returned by Read Multiple Block commands issued
>    to Type 5 tags.
> +- clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz
> +
You're adding an empty line here that is removed in the next patch.

>  
>  Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>  
> @@ -43,6 +45,8 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>  		irq-status-read-quirk;
>  		en2-rf-quirk;
>  		t5t-rmb-extra-byte-quirk;
> +		vdd_io_1v8;
This does not belong here, and so no need to remove in the next patch.

> +		clock-frequency = <27120000>;
>  		status = "okay";
>  	};
>  };
> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
> index 26c9dbb..4e051e9 100644
> --- a/drivers/nfc/trf7970a.c
> +++ b/drivers/nfc/trf7970a.c
> @@ -124,6 +124,9 @@
>  		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
>  
>  #define TRF7970A_AUTOSUSPEND_DELAY		30000 /* 30 seconds */
> +#define TRF7970A_13MHZ_CLOCK_FREQUENCY		13560000
> +#define TRF7970A_27MHZ_CLOCK_FREQUENCY		27120000
> +
>  
>  #define TRF7970A_RX_SKB_ALLOC_SIZE		256
>  
> @@ -1056,12 +1059,11 @@ static int trf7970a_init(struct trf7970a *trf)
>  
>  	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
>  
> -	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
> +	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
> +			trf->modulator_sys_clk_ctrl);
>  	if (ret)
>  		goto err_out;
>  
> -	trf->modulator_sys_clk_ctrl = 0;
> -
>  	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
>  			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
>  			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
> @@ -1181,27 +1183,37 @@ static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
>  	switch (tech) {
>  	case NFC_DIGITAL_RF_TECH_106A:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_OOK;
>  		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_106B:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_ASK10;
>  		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_212F:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_ASK10;
>  		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_424F:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_ASK10;
>  		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_ISO15693:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_OOK;
>  		trf->guard_time = TRF7970A_GUARD_TIME_15693;
>  		break;
>  	default:
> @@ -1571,17 +1583,23 @@ static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>  			TRF7970A_ISO_CTRL_NFC_CE |
>  			TRF7970A_ISO_CTRL_NFC_CE_14443A;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_OOK;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_212F:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>  			TRF7970A_ISO_CTRL_NFC_NFCF_212;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_ASK10;
>  		break;
>  	case NFC_DIGITAL_RF_TECH_424F:
>  		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>  			TRF7970A_ISO_CTRL_NFC_NFCF_424;
> -		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +		trf->modulator_sys_clk_ctrl =
> +			(trf->modulator_sys_clk_ctrl & 0xF8) |
> +			TRF7970A_MODULATOR_DEPTH_ASK10;
>  		break;
>  	default:
>  		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
> @@ -1987,6 +2005,7 @@ static int trf7970a_probe(struct spi_device *spi)
>  	struct device_node *np = spi->dev.of_node;
>  	struct trf7970a *trf;
>  	int uvolts, autosuspend_delay, ret;
> +	u32 clk_freq = 13560000;
Use TRF7970A_13MHZ_CLOCK_FREQUENCY here?

>  
>  	if (!np) {
>  		dev_err(&spi->dev, "No Device Tree entry\n");
> @@ -2043,6 +2062,15 @@ static int trf7970a_probe(struct spi_device *spi)
>  		return ret;
>  	}
>  
> +	of_property_read_u32(np, "clock-frequency", &clk_freq);
> +	if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
> +		(clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY)) {
Two comparisons with 27MHz, missing 13MHz.

> +		dev_err(trf->dev,
> +			"clock-frequency (%u Hz) unsupported\n",
> +			clk_freq);
> +		return -EINVAL;
> +	}
> +
>  	if (of_property_read_bool(np, "en2-rf-quirk"))
>  		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
>  
>
Mark Greer Dec. 20, 2016, 6:11 p.m. UTC | #2
Hi Geoff.

Please put the version in your subjects when submitting anything but the
initial version of a patch (e.g., [PATCH v2 1/3]).

Which series do you want reviewed?

Mark
--
Geoff Lansberry Dec. 20, 2016, 6:29 p.m. UTC | #3
On Tue, Dec 20, 2016 at 1:11 PM, Mark Greer <mgreer@animalcreek.com> wrote:
> Hi Geoff.
>
> Please put the version in your subjects when submitting anything but the
> initial version of a patch (e.g., [PATCH v2 1/3]).
>
> Which series do you want reviewed?
>
> Mark
> --
Sorry about the double posting, I had forgotten to erase the patches I
generated while rebasing and checking, and I'll have to figure out how
to add that v2 line to the automatically generated subject line if I
end up submitting another round.

Please review the three most recent patches, which have the send time
of 17:16.

Best Regards,
Geoff
Mark Greer Dec. 20, 2016, 6:35 p.m. UTC | #4
On Tue, Dec 20, 2016 at 01:29:13PM -0500, Geoff Lansberry wrote:
> On Tue, Dec 20, 2016 at 1:11 PM, Mark Greer <mgreer@animalcreek.com> wrote:
> > Hi Geoff.
> >
> > Please put the version in your subjects when submitting anything but the
> > initial version of a patch (e.g., [PATCH v2 1/3]).
> >
> > Which series do you want reviewed?
> >
> > Mark
> > --
> Sorry about the double posting, I had forgotten to erase the patches I
> generated while rebasing and checking, and I'll have to figure out how
> to add that v2 line to the automatically generated subject line if I
> end up submitting another round.

Hint: -v <n> option of 'git format-patch'

> Please review the three most recent patches, which have the send time
> of 17:16.

Okay, thank.

Mark
--
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
index 32b35a0..e262ac1 100644
--- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
+++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
@@ -21,6 +21,8 @@  Optional SoC Specific Properties:
 - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum
   where an extra byte is returned by Read Multiple Block commands issued
   to Type 5 tags.
+- clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz
+
 
 Example (for ARM-based BeagleBone with TRF7970A on SPI1):
 
@@ -43,6 +45,8 @@  Example (for ARM-based BeagleBone with TRF7970A on SPI1):
 		irq-status-read-quirk;
 		en2-rf-quirk;
 		t5t-rmb-extra-byte-quirk;
+		vdd_io_1v8;
+		clock-frequency = <27120000>;
 		status = "okay";
 	};
 };
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 26c9dbb..4e051e9 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -124,6 +124,9 @@ 
 		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 
 #define TRF7970A_AUTOSUSPEND_DELAY		30000 /* 30 seconds */
+#define TRF7970A_13MHZ_CLOCK_FREQUENCY		13560000
+#define TRF7970A_27MHZ_CLOCK_FREQUENCY		27120000
+
 
 #define TRF7970A_RX_SKB_ALLOC_SIZE		256
 
@@ -1056,12 +1059,11 @@  static int trf7970a_init(struct trf7970a *trf)
 
 	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
 
-	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
+	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
+			trf->modulator_sys_clk_ctrl);
 	if (ret)
 		goto err_out;
 
-	trf->modulator_sys_clk_ctrl = 0;
-
 	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
@@ -1181,27 +1183,37 @@  static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
 	switch (tech) {
 	case NFC_DIGITAL_RF_TECH_106A:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_OOK;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
 		break;
 	case NFC_DIGITAL_RF_TECH_106B:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
 		break;
 	case NFC_DIGITAL_RF_TECH_212F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
 		break;
 	case NFC_DIGITAL_RF_TECH_424F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
 		break;
 	case NFC_DIGITAL_RF_TECH_ISO15693:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_OOK;
 		trf->guard_time = TRF7970A_GUARD_TIME_15693;
 		break;
 	default:
@@ -1571,17 +1583,23 @@  static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_CE |
 			TRF7970A_ISO_CTRL_NFC_CE_14443A;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_OOK;
 		break;
 	case NFC_DIGITAL_RF_TECH_212F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_NFCF_212;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_ASK10;
 		break;
 	case NFC_DIGITAL_RF_TECH_424F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_NFCF_424;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl =
+			(trf->modulator_sys_clk_ctrl & 0xF8) |
+			TRF7970A_MODULATOR_DEPTH_ASK10;
 		break;
 	default:
 		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
@@ -1987,6 +2005,7 @@  static int trf7970a_probe(struct spi_device *spi)
 	struct device_node *np = spi->dev.of_node;
 	struct trf7970a *trf;
 	int uvolts, autosuspend_delay, ret;
+	u32 clk_freq = 13560000;
 
 	if (!np) {
 		dev_err(&spi->dev, "No Device Tree entry\n");
@@ -2043,6 +2062,15 @@  static int trf7970a_probe(struct spi_device *spi)
 		return ret;
 	}
 
+	of_property_read_u32(np, "clock-frequency", &clk_freq);
+	if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
+		(clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY)) {
+		dev_err(trf->dev,
+			"clock-frequency (%u Hz) unsupported\n",
+			clk_freq);
+		return -EINVAL;
+	}
+
 	if (of_property_read_bool(np, "en2-rf-quirk"))
 		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;