drivers: Add NXP LPC clock control driver

Add clock control driver for NXP LPC devices that use
the MCUX SDK drivers

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>

drivers/clock_control/CMakeLists.txt

@@ -7,6 +7,7 @@ zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_MCG            clock_control_mcux
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_PCC            clock_control_mcux_pcc.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_SCG            clock_control_mcux_scg.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_SIM            clock_control_mcux_sim.c)
+zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_SYSCON         clock_control_mcux_syscon.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_NPCX                clock_control_npcx.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_NRF                 clock_control_nrf.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC_CALIBRATION nrf_clock_calibration.c)

drivers/clock_control/Kconfig

@@ -38,6 +38,8 @@ source "drivers/clock_control/Kconfig.mcux_scg"
 
 source "drivers/clock_control/Kconfig.mcux_sim"
 
+source "drivers/clock_control/Kconfig.mcux_syscon"
+
 source "drivers/clock_control/Kconfig.npcx"
 
 source "drivers/clock_control/Kconfig.rv32m1"

drivers/clock_control/Kconfig.mcux_syscon

@@ -0,0 +1,10 @@
+# MCUXpresso SDK SYSCON
+
+# Copyright (c) 2020, NXP
+# SPDX-License-Identifier: Apache-2.0
+
+config CLOCK_CONTROL_MCUX_SYSCON
+	bool "MCUX LPC clock driver"
+	depends on HAS_MCUX_SYSCON
+	help
+	  Enable support for mcux clock driver.

drivers/clock_control/clock_control_mcux_syscon.c

@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2020, NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT nxp_lpc_syscon
+#include <errno.h>
+#include <soc.h>
+#include <drivers/clock_control.h>
+#include <dt-bindings/clock/mcux_lpc_syscon_clock.h>
+#include <fsl_clock.h>
+
+#define LOG_LEVEL CONFIG_CLOCK_CONTROL_LOG_LEVEL
+#include <logging/log.h>
+LOG_MODULE_REGISTER(clock_control);
+
+static int mcux_lpc_syscon_clock_control_on(const struct device *dev,
+			      clock_control_subsys_t sub_system)
+{
+	return 0;
+}
+
+static int mcux_lpc_syscon_clock_control_off(const struct device *dev,
+			       clock_control_subsys_t sub_system)
+{
+	return 0;
+}
+
+static int mcux_lpc_syscon_clock_control_get_subsys_rate(
+					const struct device *dev,
+				    clock_control_subsys_t sub_system,
+				    uint32_t *rate)
+{
+#if defined(CONFIG_I2C_MCUX_FLEXCOMM) || \
+		defined(CONFIG_SPI_MCUX_FLEXCOMM) || \
+		defined(CONFIG_UART_MCUX_FLEXCOMM)
+
+	uint32_t clock_name = (uint32_t) sub_system;
+
+	switch (clock_name) {
+	case MCUX_FLEXCOMM0_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(0);
+		break;
+	case MCUX_FLEXCOMM1_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(1);
+		break;
+	case MCUX_FLEXCOMM2_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(2);
+		break;
+	case MCUX_FLEXCOMM3_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(3);
+		break;
+	case MCUX_FLEXCOMM4_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(4);
+		break;
+	case MCUX_FLEXCOMM5_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(5);
+		break;
+	case MCUX_FLEXCOMM6_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(6);
+		break;
+	case MCUX_FLEXCOMM7_CLK:
+		*rate = CLOCK_GetFlexCommClkFreq(7);
+		break;
+	case MCUX_HS_SPI_CLK:
+#if defined(FSL_FEATURE_FLEXCOMM8_SPI_INDEX)
+		*rate = CLOCK_GetHsLspiClkFreq();
+#elif defined(FSL_FEATURE_FLEXCOMM14_SPI_INDEX)
+		*rate = CLOCK_GetFlexCommClkFreq(14);
+#else
+		LOG_ERR("Missing feature define for HS_SPI clock!");
+#endif
+		break;
+	}
+#endif
+
+	return 0;
+}
+
+static int mcux_lpc_syscon_clock_control_init(const struct device *dev)
+{
+	return 0;
+}
+
+static const struct clock_control_driver_api mcux_lpc_syscon_api = {
+	.on = mcux_lpc_syscon_clock_control_on,
+	.off = mcux_lpc_syscon_clock_control_off,
+	.get_rate = mcux_lpc_syscon_clock_control_get_subsys_rate,
+};
+
+#define LPC_CLOCK_INIT(n) \
+	\
+DEVICE_AND_API_INIT(mcux_lpc_syscon_##n, DT_INST_LABEL(n), \
+		    &mcux_lpc_syscon_clock_control_init, \
+		    NULL, NULL, \
+		    PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
+		    &mcux_lpc_syscon_api);
+
+DT_INST_FOREACH_STATUS_OKAY(LPC_CLOCK_INIT)