Cal. Civ. Code § 1954

(a) A landlord may enter the dwelling unit only in the following cases:
(1) In case of emergency.
(2) To make necessary or agreed repairs, decorations, alterations or improvements, supply necessary or agreed services, or exhibit the dwelling unit to prospective or actual purchasers,
mortgagees, tenants, workers, or contractors or to make an inspection pursuant to subdivision (f) of Section 1950.5.
(3) When the tenant has abandoned or surrendered the premises.
(4) Pursuant to court order.
(5) For the purposes set forth in Chapter 2.5 (commencing with Section 1954.201).
(6) To comply with the provisions of Article 2.2 (commencing with Section 17973) of Chapter 5 of Part 1.5 of Division 13 of the Health and Safety Code.
(b) Except in cases of emergency or when the tenant has abandoned or surrendered the premises, entry may not be made during other than normal business hours unless the tenant consents to an entry during other than normal business hours at the time of
entry.
(c) The landlord may not abuse the right of access or use it to harass the tenant.
(d) (1) Except as provided in subdivision (e), or as provided in paragraph (2) or (3), the landlord shall give the tenant reasonable notice in writing of his or her intent to enter and enter only during normal business hours. The notice shall include the date, approximate time, and purpose of the entry. The notice may be personally delivered to the tenant, left with someone of a suitable age and discretion at the premises, or, left on, near, or under the usual entry door of the premises in a manner in which a reasonable person would discover the notice. Twenty-four hours shall be presumed to be reasonable notice in absence of evidence to the contrary. The notice may be mailed to the tenant. Mailing of the notice at least six days prior to an intended entry is presumed
reasonable notice in the absence of evidence to the contrary.
(2) If the purpose of the entry is to exhibit the dwelling unit to prospective or actual purchasers, the notice may be given orally, in person or by telephone, if the landlord or his or her agent has notified the tenant in writing within 120 days of the oral notice that the property is for sale and that the landlord or agent may contact the tenant orally for the purpose described above. Twenty-four hours is presumed reasonable notice in the absence of evidence to the contrary. The notice shall include the date, approximate time, and purpose of the entry. At the time of entry, the landlord or agent shall leave written evidence of the entry inside the unit.
(3) The tenant and the landlord may agree orally to an entry to make agreed repairs or supply agreed services. The agreement shall include the date and approximate
time of the entry, which shall be within one week of the agreement. In this case, the landlord is not required to provide the tenant a written notice.
(e) No notice of entry is required under this section:
(1) To respond to an emergency.
(2) If the tenant is present and consents to the entry at the time of entry.
(3) After the tenant has abandoned or surrendered the unit.