pwm: Add snapshot of QTI PWM LPG driver

The QTI PWM LPG driver supports the configuration of PWM/LPG channels on
QTI PMICs.

This is a snapshot of the driver taken from msm-4.19 as of commit
cf2cbb63fb60 ("Merge "input: touchscreen: synaptics_tcm: enable touch
driver"") with the following modifications:
  - Remove config_extend callback and pwm_get_period_extend()
  - Remove struct output_pattern and all its references
  - Remove enable, disable and config pwm_ops callbacks and instead use
    only apply()
  - Remove output_type callbacks
  - Remove support for dbg_show callback

Change-Id: I28571a8c6d5b0d5ac0cad113e77f3b5de8bf97c4
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
[quic_collinsd@quicinc.com: fixed "sychronization" typo]
Signed-off-by: David Collins <quic_collinsd@quicinc.com>

drivers/pwm/Kconfig

@@ -432,6 +432,16 @@ config PWM_PXA
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-pxa.
 
+config PWM_QTI_LPG
+	tristate "Qualcomm Technologies, Inc. LPG driver"
+	depends on MFD_SPMI_PMIC && OF
+	help
+	  This driver supports the LPG (Light Pulse Generator) module found in
+	  Qualcomm Technologies, Inc. PMIC chips. Each LPG channel can be
+	  configured to operate in PWM mode to output a fixed amplitude with
+	  variable duty cycle or in LUT (Look up table) mode to output PWM
+	  signal with a modulated amplitude.
+
 config PWM_RASPBERRYPI_POE
 	tristate "Raspberry Pi Firwmware PoE Hat PWM support"
 	# Make sure not 'y' when RASPBERRYPI_FIRMWARE is 'm'. This can only

drivers/pwm/Makefile

@@ -39,6 +39,7 @@ obj-$(CONFIG_PWM_NTXEC)		+= pwm-ntxec.o
 obj-$(CONFIG_PWM_OMAP_DMTIMER)	+= pwm-omap-dmtimer.o
 obj-$(CONFIG_PWM_PCA9685)	+= pwm-pca9685.o
 obj-$(CONFIG_PWM_PXA)		+= pwm-pxa.o
+obj-$(CONFIG_PWM_QTI_LPG)	+= pwm-qti-lpg.o
 obj-$(CONFIG_PWM_RASPBERRYPI_POE)	+= pwm-raspberrypi-poe.o
 obj-$(CONFIG_PWM_RCAR)		+= pwm-rcar.o
 obj-$(CONFIG_PWM_RENESAS_TPU)	+= pwm-renesas-tpu.o