From 31f88a2d0e23f1e27d0ef40427f271c2050249e8 Mon Sep 17 00:00:00 2001
From: Benjamin Valentin <benjamin.valentin@ml-pa.com>
Date: Fri, 29 Mar 2019 13:39:34 +0100
Subject: [PATCH 1/3] sam0_common: periph/spi: use sercom_clk_en/dis()

Use already existing functions to turn on / off SERCOM clocks instead
of replicating the functionality in the driver.
---
 cpu/sam0_common/periph/spi.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/cpu/sam0_common/periph/spi.c b/cpu/sam0_common/periph/spi.c
index 551798c36f..cbd48ae1f1 100644
--- a/cpu/sam0_common/periph/spi.c
+++ b/cpu/sam0_common/periph/spi.c
@@ -48,20 +48,12 @@ static inline SercomSpi *dev(spi_t bus)
 
 static inline void poweron(spi_t bus)
 {
-#if defined(CPU_FAM_SAMD21)
-    PM->APBCMASK.reg |= (PM_APBCMASK_SERCOM0 << sercom_id(dev(bus)));
-#elif defined(CPU_SAML21) || defined(CPU_SAML1X)
-    MCLK->APBCMASK.reg |= (MCLK_APBCMASK_SERCOM0 << sercom_id(dev(bus)));
-#endif
+    sercom_clk_en(dev(bus));
 }
 
 static inline void poweroff(spi_t bus)
 {
-#if defined(CPU_FAM_SAMD21)
-    PM->APBCMASK.reg &= ~(PM_APBCMASK_SERCOM0 << sercom_id(dev(bus)));
-#elif defined(CPU_SAML21) || defined(CPU_SAML1X)
-    MCLK->APBCMASK.reg &= ~(MCLK_APBCMASK_SERCOM0 << sercom_id(dev(bus)));
-#endif
+    sercom_clk_dis(dev(bus));
 }
 
 void spi_init(spi_t bus)

From 84233ce5d519aba8b3eeee3ec2083300b0de6d46 Mon Sep 17 00:00:00 2001
From: Benjamin Valentin <benjamin.valentin@ml-pa.com>
Date: Fri, 29 Mar 2019 15:03:54 +0100
Subject: [PATCH 2/3] sam0_common: replace sercom_id() calculation with switch
 statement

As the sercom_id() function grows it gets more unweidly.
Let's replace it with a simple switch statement that is true for all
sam0 parts.
---
 cpu/sam0_common/include/periph_cpu_common.h | 42 +++++++++++++++++----
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/cpu/sam0_common/include/periph_cpu_common.h b/cpu/sam0_common/include/periph_cpu_common.h
index ac3fe8edd0..8039b83109 100644
--- a/cpu/sam0_common/include/periph_cpu_common.h
+++ b/cpu/sam0_common/include/periph_cpu_common.h
@@ -323,16 +323,42 @@ void gpio_init_mux(gpio_t pin, gpio_mux_t mux);
  *
  * @return              numeric id of the given SERCOM device
  */
-static inline int sercom_id(void *sercom)
+static inline int sercom_id(const void *sercom)
 {
-#if defined(CPU_FAM_SAMD21)
-    return ((((uint32_t)sercom) >> 10) & 0x7) - 2;
-#elif defined (CPU_FAM_SAML10) || defined (CPU_FAM_SAML11)
-    return ((((uint32_t)sercom) >> 10) & 0x7) - 1;
-#elif defined(CPU_FAM_SAML21) || defined(CPU_FAM_SAMR30)
-    /* Left side handles SERCOM0-4 while right side handles unaligned address of SERCOM5 */
-    return ((((uint32_t)sercom) >> 10) & 0x7) + ((((uint32_t)sercom) >> 22) & 0x04);
+#ifdef SERCOM0
+    if (sercom == SERCOM0)
+        return 0;
 #endif
+#ifdef SERCOM1
+    if (sercom == SERCOM1)
+        return 1;
+#endif
+#ifdef SERCOM2
+    if (sercom == SERCOM2)
+        return 2;
+#endif
+#ifdef SERCOM3
+    if (sercom == SERCOM3)
+        return 3;
+#endif
+#ifdef SERCOM4
+    if (sercom == SERCOM4)
+        return 4;
+#endif
+#ifdef SERCOM5
+    if (sercom == SERCOM5)
+        return 5;
+#endif
+#ifdef SERCOM6
+    if (sercom == SERCOM6)
+        return 6;
+#endif
+#ifdef SERCOM7
+    if (sercom == SERCOM7)
+        return 7;
+#endif
+
+    return -1;
 }
 
 /**

From 7415e0590ebc6ccbbb6d61145073b72704541392 Mon Sep 17 00:00:00 2001
From: Benjamin Valentin <benjamin.valentin@ml-pa.com>
Date: Tue, 2 Apr 2019 18:01:24 +0200
Subject: [PATCH 3/3] sam0_common: spi: use sercom_set_gen() instead of
 re-implementing it

Don't repeat yourself and introduce errors in doing so.
---
 cpu/sam0_common/periph/spi.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/cpu/sam0_common/periph/spi.c b/cpu/sam0_common/periph/spi.c
index cbd48ae1f1..43a9f105a7 100644
--- a/cpu/sam0_common/periph/spi.c
+++ b/cpu/sam0_common/periph/spi.c
@@ -76,13 +76,10 @@ void spi_init(spi_t bus)
            (dev(bus)->SYNCBUSY.reg & SERCOM_SPI_SYNCBUSY_SWRST));
 
     /* configure base clock: using GLK GEN 0 */
-#if defined(CPU_FAM_SAMD21)
-    GCLK->CLKCTRL.reg = (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 |
-                         (SERCOM0_GCLK_ID_CORE + sercom_id(dev(bus))));
-    while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY) {}
-#elif defined(CPU_SAML21) || defined(CPU_SAML1X)
-    GCLK->PCHCTRL[SERCOM0_GCLK_ID_CORE + sercom_id(dev(bus))].reg =
-                                (GCLK_PCHCTRL_CHEN | GCLK_PCHCTRL_GEN_GCLK0);
+#ifdef GCLK_CLKCTRL_GEN_GCLK0
+    sercom_set_gen(dev(bus), GCLK_CLKCTRL_GEN_GCLK0);
+#else
+    sercom_set_gen(dev(bus), GCLK_PCHCTRL_GEN_GCLK0);
 #endif
 
     /* enable receiver and configure character size to 8-bit