From 5d72b2217199f55c1e5e1ce4d1d3ba36f28de533 Mon Sep 17 00:00:00 2001
From: Eve Redero <eve.redero@gmail.com>
Date: Tue, 5 Mar 2024 21:42:21 +0100
Subject: [PATCH] wip: start writing drivers

---
 drivers/cc2500/cc2500.c                 | 110 +++++++++++++++++++++++-
 drivers/cc2500/cc2500_defines.h         | 109 +++++++++++++++++++++++
 dts/bindings/propy_radio/ti,cc2500.yaml |   8 +-
 3 files changed, 221 insertions(+), 6 deletions(-)

diff --git a/drivers/cc2500/cc2500.c b/drivers/cc2500/cc2500.c
index ab34ec8..6648171 100644
--- a/drivers/cc2500/cc2500.c
+++ b/drivers/cc2500/cc2500.c
@@ -21,12 +21,115 @@ LOG_MODULE_REGISTER(cc2500, CONFIG_CC2500_LOG_LEVEL);
 
 struct cc2500_config {
 	const struct spi_dt_spec spi;
-	struct gpio_dt_spec ce;
+	const uint8_t array[40];
+	const int array_len;
 };
 
 struct cc2500_data {
 };
 
+/* Private core communication functions */
+uint8_t cc2500_write_register(const struct device *dev, uint8_t reg, uint8_t data)
+{
+	/* Register config can only be done in power down or standby */
+	const struct cc2500_config *config = dev->config;
+	uint8_t tx_data[2];
+	uint8_t rx_data = 0;
+	int ret;
+	const struct spi_buf tx_buf[1] = {
+		{
+			.buf = tx_data,
+			.len = 2
+		}
+	};
+	const struct spi_buf rx_buf[1] = {
+		{
+			.buf = &rx_data,
+			.len = 2
+		}
+	};
+	struct spi_buf_set tx = {
+		.buffers = tx_buf,
+		.count = 1
+	};
+	const struct spi_buf_set rx = {
+		.buffers = rx_buf,
+		.count = 1
+	};
+
+	// 5 lower bits for address, the 6th is 0 for read and 1 for write
+	tx_data[0] = ( WRITE_SINGLE | ( RW_MASK & reg ) );
+	tx_data[1] = data;
+
+	ret = spi_transceive_dt(&config->spi, &tx, &rx);
+	if (ret) {
+		LOG_ERR("Error transceive %d", ret);
+		return 0;
+	}
+	return rx_data;
+}
+
+uint8_t cc2500_read_register(const struct device *dev, uint8_t reg)
+{
+	const struct cc2500_config *config = dev->config;
+	uint8_t tx_data[2];
+	uint8_t rx_data[2];
+	int ret;
+	const struct spi_buf tx_buf[1] = {
+		{
+			.buf = tx_data,
+			.len = 2
+		}
+	};
+	const struct spi_buf rx_buf[1] = {
+		{
+			.buf = (void *)rx_data,
+			.len = 2
+		}
+	};
+	struct spi_buf_set tx = {
+		.buffers = tx_buf,
+		.count = 1
+	};
+	const struct spi_buf_set rx = {
+		.buffers = rx_buf,
+		.count = 1
+	};
+
+	// 5 lower bits for address, the 6th is 0 for read and 1 for write
+	tx_data[0] = ( READ_SINGLE | ( RW_MASK & reg ) );
+	tx_data[1] = NOP;
+
+	ret = spi_transceive_dt(&config->spi, &tx, &rx);
+
+	if (ret) {
+		LOG_ERR("Error transceive %d", ret);
+		return 0;
+	}
+
+	// status is 1st byte of receive buffer
+	return rx_data[1];
+}
+
+static int cc2500_set_config_registers(const struct device *dev)
+{
+	int ret = 0;
+	int i, reg;
+	const struct cc2500_config *config = dev->config;
+
+	if (config->array_len < 40) {
+		LOG_DBG("No valid default config");
+		/* No valid startup config */
+		return 0;
+	}
+	for (i=0; i<40; i++) {
+		cc2500_write_register(dev, i+0x07, config->array[i]);
+	}
+	return ret;
+}
+
+/* API functions */
+
 static int cc2500_read(const struct device *dev, uint8_t *buffer, uint8_t data_len)
 {
 	int ret = 0;
@@ -67,6 +170,8 @@ static int cc2500_init(const struct device *dev)
 		return ret;
 	}
 
+	cc2500_set_config_registers(dev);
+
 	return 0;
 }
 
@@ -75,7 +180,8 @@ static int cc2500_init(const struct device *dev)
 #define CC2500_DEFINE(i)                                               \
 	static const struct cc2500_config cc2500_config_##i = {          \
 		.spi = SPI_DT_SPEC_INST_GET(i, CC2500_SPI_MODE, 2),            \
-		.ce = GPIO_DT_SPEC_INST_GET(i, ce_gpios),                        \
+		.array = DT_INST_PROP_OR(i, conf_array, {}), \
+		.array_len = DT_INST_PROP_LEN_OR(i, conf_array, 0), \
 	};                                                                            \
                                                                                   \
 	static struct cc2500_data cc2500_##i = {                                  \
diff --git a/drivers/cc2500/cc2500_defines.h b/drivers/cc2500/cc2500_defines.h
index e69de29..39b1925 100644
--- a/drivers/cc2500/cc2500_defines.h
+++ b/drivers/cc2500/cc2500_defines.h
@@ -0,0 +1,109 @@
+/*
+Description:  This file contains definitions specific to the CC1100/2500.
+The configuration registers, strobe commands, and status registers are
+defined, as well as some common masks for these registers.
+MSP430/CC1100-2500 Interface Code Library v1.0
+K. Quiring
+Texas Instruments, Inc.
+July 2006
+IAR Embedded Workbench v3.41
+*/
+
+/* Configuration Registers */
+#define IOCFG2       0x00        /* GDO2 output pin configuration */
+#define IOCFG1       0x01        /* GDO1 output pin configuration */
+#define IOCFG0       0x02        /* GDO0 output pin configuration */
+#define FIFOTHR      0x03        /* RX FIFO and TX FIFO thresholds */
+#define SYNC1        0x04        /* Sync word, high byte */
+#define SYNC0        0x05        /* Sync word, low byte */
+#define PKTLEN       0x06        /* Packet length */
+#define PKTCTRL1     0x07        /* Packet automation control */
+#define PKTCTRL0     0x08        /* Packet automation control */
+#define ADDR         0x09        /* Device address */
+#define CHANNR       0x0A        /* Channel number */
+#define FSCTRL1      0x0B        /* Frequency synthesizer control */
+#define FSCTRL0      0x0C        /* Frequency synthesizer control */
+#define FREQ2        0x0D        /* Frequency control word, high byte */
+#define FREQ1        0x0E        /* Frequency control word, middle byte */
+#define FREQ0        0x0F        /* Frequency control word, low byte */
+#define MDMCFG4      0x10        /* Modem configuration */
+#define MDMCFG3      0x11        /* Modem configuration */
+#define MDMCFG2      0x12        /* Modem configuration */
+#define MDMCFG1      0x13        /* Modem configuration */
+#define MDMCFG0      0x14        /* Modem configuration */
+#define DEVIATN      0x15        /* Modem deviation setting */
+#define MCSM2        0x16        /* Main Radio Cntrl State Machine config */
+#define MCSM1        0x17        /* Main Radio Cntrl State Machine config */
+#define MCSM0        0x18        /* Main Radio Cntrl State Machine config */
+#define FOCCFG       0x19        /* Frequency Offset Compensation config */
+#define BSCFG        0x1A        /* Bit Synchronization configuration */
+#define AGCCTRL2     0x1B        /* AGC control */
+#define AGCCTRL1     0x1C        /* AGC control */
+#define AGCCTRL0     0x1D        /* AGC control */
+#define WOREVT1      0x1E        /* High byte Event 0 timeout */
+#define WOREVT0      0x1F        /* Low byte Event 0 timeout */
+#define WORCTRL      0x20        /* Wake On Radio control */
+#define FREND1       0x21        /* Front end RX configuration */
+#define FREND0       0x22        /* Front end TX configuration */
+#define FSCAL3       0x23        /* Frequency synthesizer calibration */
+#define FSCAL2       0x24        /* Frequency synthesizer calibration */
+#define FSCAL1       0x25        /* Frequency synthesizer calibration */
+#define FSCAL0       0x26        /* Frequency synthesizer calibration */
+#define RCCTRL1      0x27        /* RC oscillator configuration */
+#define RCCTRL0      0x28        /* RC oscillator configuration */
+#define FSTEST       0x29        /* Frequency synthesizer cal control */
+#define PTEST        0x2A        /* Production test */
+#define AGCTEST      0x2B        /* AGC test */
+#define TEST2        0x2C        /* Various test settings */
+#define TEST1        0x2D        /* Various test settings */
+#define TEST0        0x2E        /* Various test settings */
+
+/* Strobe commands */
+#define SRES         0x30        /* Reset chip. */
+#define SFSTXON      0x31        /* Enable/calibrate freq synthesizer */
+#define SXOFF        0x32        /* Turn off crystal oscillator. */
+#define SCAL         0x33        /* Calibrate freq synthesizer & disable */
+#define SRX          0x34        /* Enable RX. */
+#define STX          0x35        /* Enable TX. */
+#define SIDLE        0x36        /* Exit RX / TX */
+#define SAFC         0x37        /* AFC adjustment of freq synthesizer */
+#define SWOR         0x38        /* Start automatic RX polling sequence */
+#define SPWD         0x39        /* Enter pwr down mode when CSn goes hi */
+#define SFRX         0x3A        /* Flush the RX FIFO buffer. */
+#define SFTX         0x3B        /* Flush the TX FIFO buffer. */
+#define SWORRST      0x3C        /* Reset real time clock. */
+#define SNOP         0x3D        /* No operation. */
+
+/* Status registers */
+#define PARTNUM      0x30        /* Part number */
+#define VERSION      0x31        /* Current version number */
+#define FREQEST      0x32        /* Frequency offset estimate */
+#define LQI          0x33        /* Demodulator estimate for link quality */
+#define RSSI         0x34        /* Received signal strength indication */
+#define MARCSTATE    0x35        /* Control state machine state */
+#define WORTIME1     0x36        /* High byte of WOR timer */
+#define WORTIME0     0x37        /* Low byte of WOR timer */
+#define PKTSTATUS    0x38        /* Current GDOx status and packet status */
+#define VCO_VC_DAC   0x39        /* Current setting from PLL cal module */
+#define TXBYTES      0x3A        /* Underflow and # of bytes in TXFIFO */
+#define RXBYTES      0x3B        /* Overflow and # of bytes in RXFIFO */
+#define NUM_RXBYTES  0x7F        /* Mask "# of bytes" field in _RXBYTES */
+
+/* Other memory locations */
+#define PATABLE      0x3E
+#define TXFIFO       0x3F
+#define RXFIFO       0x3F
+
+/* Masks for appended status bytes */
+#define LQI_RX       0x01        /* Position of LQI byte */
+#define CRC_OK       0x80        /* Mask "CRC_OK" bit within LQI byte */
+
+/* Byte used as TX when reading */
+#define NOP          0xFF
+
+/* Definitions to support burst/single access: */
+#define RW_MASK      0xC0        /* Mask register for single or burst */
+#define WRITE_SINGLE 0x00
+#define WRITE_BURST  0x40
+#define READ_SINGLE  0x80
+#define READ_BURST   0xC0
diff --git a/dts/bindings/propy_radio/ti,cc2500.yaml b/dts/bindings/propy_radio/ti,cc2500.yaml
index 29e478f..c4fbcd5 100644
--- a/dts/bindings/propy_radio/ti,cc2500.yaml
+++ b/dts/bindings/propy_radio/ti,cc2500.yaml
@@ -12,8 +12,8 @@ properties:
   reg:
     required: true
 
-  ce-gpios:
-    type: phandle-array
-    required: true
+  conf-array:
+    type: uint8-array
     description: |
-      Chip Enable GPIO (active high). It is used to activate the chip RX or TX mode. If not configured, the driver will use three-wires behaviour and multiplex with the SPI CSN signal.
+      Configuration values from 0x07 to 0x2E.
+      By default, device keeps its default conf values.